Database Develop

Charging battery while using TomTom 6 in the car

Hello everybody,
i wonder if any of you encountered the problem of not charging the battery in the car while using TomTom 6. It happened to me many times and it's quite annoying because at a certain point the phone will go off and it will need to be charged while off otherwise it will not work.
Since it happened in different cars it does not depend by the charger but has to be a software problem either of WM or TomTom.
Any suggestion?
Thanks!
Panco

Buy a decent charger with at least 2A.

2A? 1A should be more than enough...
(I'm not sure you'd be able to find a 2A USB charger as the USB2.0 spec requires connectors to be rated at 1.5A tops so if there was such a beast I personally wouldn't touch it)
Mathew

Do a careful inspection of the USB connector on the phone and the car cradles/leads - my money is on a piece of cloth/fluff etc breaking the charger connection.

Today, I tried using CoPilot (with a live internet connection going for Traffic updates), with bluetooth switched on (so that I could connect with my Parrot kit in the car), and the phone on charge.
On the journey back home, CoPilot was running (and on the screen) whilst I was on a call via the Parrot. And yet, the battery was still getting charged properly! I was actually impressed that the charging would work automatically once the cable was inserted - my MDA Pro needed the display to be off before I could see the red charging light come on and for the phone to start charging.
FYI, the charger was a cigar_lighter_adapter-2-USB_cable type.
I've got an MDA Compact IV with the original ROM (but TouchFlo tweaks, etc).
So, I'd say either there's something wrong with your adapter, cable, or indeed TomTom is using a lot of juice!

panco said:
Hello everybody,
i wonder if any of you encountered the problem of not charging the battery in the car while using TomTom 6. It happened to me many times and it's quite annoying because at a certain point the phone will go off and it will need to be charged while off otherwise it will not work.
Since it happened in different cars it does not depend by the charger but has to be a software problem either of WM or TomTom.
Any suggestion?
Thanks!
Panco
Click to expand...
Click to collapse
No, it does this with most GPS SW and the problem is heating preventing battery charging to avoid the battery to catch fire, especially with the the phone placed in the windscreen with the sun on it. At night the issue is no longer an issue. So when you have a break for coffee let the phone have a break too to cool down and recharge.

Or mount it infront of an air con vent

Nuri58 said:
No, it does this with most GPS SW and the problem is heating preventing battery charging to avoid the battery to catch fire, especially with the the phone placed in the windscreen with the sun on it. At night the issue is no longer an issue. So when you have a break for coffee let the phone have a break too to cool down and recharge.
Click to expand...
Click to collapse
Thank for your post, i think you got the point with something (the heating of the battery+gps) preventing the battery to recharge; i'm convinced of this because the problem is not always present but it comes at certain conditions.
I'll try to let the diamond cool down at regular intervals and not to position too exposed. I also noticed that it's advisable to first connect the phone to the charger then after some minutes run the tomtom otherwise the problem is likely to happen.
Thanks to all.
Panco

There are many tool available to show you the internal temperature of the device - the battery monitor 'Batti' is one such tool (and it's free).
Give something like that a try then you'll be able to see if your problems bear any correlation with temperature.
Mathew

Im experiencing the same with Garmin, yes, it was hot...first I thought the cigarette-to-usb-adapter was not strong enough....
Will try to keep it cool

You need a USB car charger with at least 1A, as said in previous post, but with any USB cable the current limiting will be lways be 500mA.
Only the original Diamond cable will allow you to charge with currents over 500mA. To measure the charge current you can use several programs, like my TodayWarrior (as it is a plugin you will need to disable temporarilt Touch Flo or use Second Today).

It's not heating of battery, but just that when Using tomtom, with backlight, Full GPS usage, phone on and that VGA screen just pulls more than your charger can bring
Got the same issue, and yes, as said before, get a heavier charger.

I have the same problem using IGO8.
First point, using Full GPS in car will consumme a lot of energy.
So it's better to use a 2A/5V charger (5V is the important thing ... And for your information, HTC is selling 2A car charger for their last phones ...)
Second point, the GPS chip is badly placed in the phone, behind the battery.
So yes, when the GPS is used for a long time, it makes the battery hot and the phone stops the battery charging ...
The point is to use a good car craddle, one that lets the phone "breath" (one that doesn't cover to much the rear of the phone) ...

beemerTPPC said:
You need a USB car charger with at least 1A, as said in previous post, but with any USB cable the current limiting will be lways be 500mA.
Only the original Diamond cable will allow you to charge with currents over 500mA. To measure the charge current you can use several programs, like my TodayWarrior (as it is a plugin you will need to disable temporarilt Touch Flo or use Second Today).
Click to expand...
Click to collapse
The input sideon car chargers inclusive of HTC is 500 mA at 12 V and the output side 1A at 5V, which is what the phone requires and all car chargers I have do. But the important thing about ion-lit batteries is that they require very controlled charging conditions (contrary to the older Metal or Cadnium). E.g. If the battery is completely flat (2 V or below) it is extremely hard to recharge and will require several hours in the charger while building up the voltage to about 3.2V, only then normal charge will start. Sometimes the stand-by consumption of a phone makes it imposible to recharge it while in the phone, and requires an external recharger. This may explain the observatiobn that it is better to wait a couple of minutes before starting TT after connecting to the recharger to ensure correct initial charging.
Riel said:
It's not heating of battery, but just that when Using tomtom, with backlight, Full GPS usage, phone on and that VGA screen just pulls more than your charger can bring
Got the same issue, and yes, as said before, get a heavier charger.
Click to expand...
Click to collapse
This is the way to get a battery to explode, but fortunately the phone will not allow charging to take place and adding more amps will possibly increase heating and just worsen the situation. But correct as more power the device draws as hotter it gets and as sooner charging stops.
As Nani says there is an element of disign problem (cannot be a surprice to HTC that people actually will like to use the Navigation also on long drives), so if placed so it can cool will defenetly help. So will dimming the display to the minimum.

Car chargers bricking Kaisers

What exactly is the scoop on this? Is it that they overpower the charging circuit (everyone says they charge the phones faster)? Is there a way to tell you're about to do damage?
I don't use the car charger that came with my Kaiser, I have several generic chargers which all work just fine. However I noticed that when running GPS, although the charge light was on, the battery wouldn't really charge. It wouldn't discharge either, I put it up to the extra drain on the phone's power system.
The other day though, my phone... stopped charging? I was driving (GPS) and the phone suddenly beeped a critical battery warning, the charge light was off... but the power was plugged in and the charger's power light in the cigarette socket was on. It WAS making a connection to the phone: if I unplugged it the screen would go dimmer, if I plugged it back in it would get brighter. But it still seemed to be running off the battery, which was draining regardless. The moment I got to my destination, it all powered off. Is this a forewarning of darker circumstances to come?

from what I've read you should not be using generic chargers. The amperage could differ. Therefore, if the electricity in your vehicle spikes you could be riding with a paper weight.
In addition, it is common that your device will not charge (nor discharge) while running your gps application. I play monopoly often while my phone is in the charger and my device usually doesn't charge while I am playing.

Also, I think the pinout on generic USB chargers are different. The ones that are for Moto Razr / Blackberry phones dont work to charge the phones ( as I have a work blackberry and tried it) It didnt hurt my phone, however it just didnt charge. I have heard of others damaging but if its not made for the kaiser, I wouldn't try it.

I've never had access to Moto Razr / Blackberry chargers. While I can't speak for those, I know generic USB chargers would have exactly the same pinout as the stock Kaiser charger. The amperage supplied may indeed differ, I think that might have explained my issue above. It was almost like the charge circuit 'gave up' since the phone was demanding as much/more power as it was getting.

CrArc said:
I've never had access to Moto Razr / Blackberry chargers. While I can't speak for those, I know generic USB chargers would have exactly the same pinout as the stock Kaiser charger. The amperage supplied may indeed differ, I think that might have explained my issue above. It was almost like the charge circuit 'gave up' since the phone was demanding as much/more power as it was getting.
Click to expand...
Click to collapse
My razr charger works perfect with my tilt.. (MOTOROLLA branded - not generic)

Ditto on the motorola razr charger;Have an old razr charger I use it for travelling instead of unplugging my original;works fine!!

+2 on the Motorola branded car charger...charges my Tilt just fine. Now I'm paranoid, though...

CrArc said:
What exactly is the scoop on this? Is it that they overpower the charging circuit (everyone says they charge the phones faster)? Is there a way to tell you're about to do damage?
I don't use the car charger that came with my Kaiser, I have several generic chargers which all work just fine. However I noticed that when running GPS, although the charge light was on, the battery wouldn't really charge. It wouldn't discharge either, I put it up to the extra drain on the phone's power system.
The other day though, my phone... stopped charging? I was driving (GPS) and the phone suddenly beeped a critical battery warning, the charge light was off... but the power was plugged in and the charger's power light in the cigarette socket was on. It WAS making a connection to the phone: if I unplugged it the screen would go dimmer, if I plugged it back in it would get brighter. But it still seemed to be running off the battery, which was draining regardless. The moment I got to my destination, it all powered off. Is this a forewarning of darker circumstances to come?
Click to expand...
Click to collapse
That is the exact same thing I am experiencing with my Tilt.
Tilt is charging from a generic car-to-USB and USB cable.
I start TomTom.
Charging works fine for a while.
Then suddenly the charging stops and the battery is drained.
I found only two ways to get it to charge again:
1. Turn off device with TomTom charging; hold Tilt against cool air flowing from AC; plug into charger (while still off) ... then the phone turns on and charges.
2. Take out the battery; put it back in ... start phone.

It does seem that either the phone can draw power faster than a USB charger can supply it or the use of wifi and gps whilst charging overheats it. I particularly see this behavior when I'm running tomtom and navizon. The phone seems to remain charging longer in cooler weather or if I point an air vent at it. My current no wifi woes started after an occurrence of just this behaviour the other day.

RAZR chargers don't have enough current and it doesn't keep a positive charge when using the GPS. It says it's charging but ultimately it goes down. Sometimes it stops charging and I had to unplug it and plug it back in. Use a charger made for the Kaiser. The charger from my brother's bluetooth GPS works fine though.

I have a generic USB cigar lighter adapter which I have been using to power mine with no problem. The only way I can see a charger frying a phone is if there is a voltage spike that isn't regulated.

The charger needs to be rated with an output of 5v 2amps which is what the electric charger is rated at. Bought one off ebay for $6. Most car chargers are rated quite a bit lower (400ma).

As the previous post states, some chargers are rated at under 500ma. This is not enough to change the Kaiser... I find that the Blackberry charger works fine, but sometimes takes a very long time to charge as the current isn't quite enough. I have a generic one at about 1000ma and that works fine.
USB from a PC is normally 500ma sustained.

I think there's another thread or 2 about this somewhere. I've been having the same problem with the Kaiser not charging via generic and razr car chargers.
After seeing the other thread I bought an HTC charger from ebay - at least it looks like one and is advertised as one! The sticker on the 'real' HTC charger only says 0.5 amp (same as the others are rated), but charges no problem with TomTom going.
I tried measuring the current using different chargers and PowerGuard and I think there is a definite difference (although not an easy thing to interpret). I notice the cable is significantly heavier on the real HTC charger (also coiled and tends to drag the phone from where I mount it a little). Others have said the pinouts are different too.
I looked for a 2amp charger but couldn't find one (if anyone knows a source?).
It's an intriguing problem but a 'real' HTC charger seems to fix it.
The other thread: http://forum.xda-developers.com/showthread.php?t=406771

There were a range of brodit car mounts with built-in chargers that bricked the kaiser. I bought one and it instantly blew it's fuse. I replace the fuse and it blew my kaiser up instead.
Assuming it was the kaiser I had it replaced, only for the charger to blow it up again.
Since then I contacted dsldevelopments (UK Distributor) who replaced it with an updated model. I have not had any issues after that.

I had this problem (Kaiser not charging in the car when GPS is on) and resolved it totally by getting the offical HTC car charger. Although output is 0.5A it is rated to 2A - my previous generic car charger was only rated to one amp and that would work fine as long I wasn't using GPS but once I ran GPS it just couldn't cope. Definately resolved this problem with the official HTC car charger (got mine of flea bay for £8)
cheers
Barney

I've had no problem with designed-for-Moto chargers and ones specifically designed to charge over USB from a dumb charger.
The problem is that drawing more than 100 mA without negotiating a connection with a PC violates the USB specification. Many manufacturers have gotten around this by finding other ways to signal the presence of a "dumb" charger, telling the phone it can draw more than 100 mA.
In the case of Mini-USB devices like the Motos, Blackberries, and HTC devices, the Mini-USB connector has a fifth pin that is normally not connected. If the charger plug grounds this pin, it signals to the device that it is permitted to draw more than 100 mA without a PC connection.
If you get a charger that does not ground this pin, an HTC device will not charge rapidly, if at all. (Typically only charges slowly when screen is off). This is why you get two cables when you order a single MiniSync from BoxWave, for example. They give you one "Sync and charge from PC" cable (no pin grounded) and one "Charge only" cable (pin grounded for dumb chargers). (If the pin is grounded it interferes with data communications for most devices.)

I use a motorola charger, which is fine if you do not use GPS.
when I use the GPS after some time the battery is very hot and stops load, but if I put the cell in front of the AC, just cools again to load.
I think the problem is due to protection from overheating battery

Belkin Charger
I grabbed a Belkin charger for my KRAZR/RAZR phones and it seems to work just fine, even with GPS running. My official Moto one also works fine with the tilt in GPS mode.
I do notice, though, that no matter what I'm using to charge it with, with GPS it gets hot. Since Li-Ion batteries are supposed to stop charging at a certain temp, it's possible that the combination of a lower grade charger and the heat generated by using GPS/WiFi/Cell at the same time (or any combo of the three), might be the issue.

USB Charging So Slow Almost Not Worth It

Is anyone else having this problem?
Any work around to having it actually charge the battery up?

it uses electricity faster than its recharging its crap! ive never known any device do this. When im low on battery and have it connected to my computer i have to switch it to the mains for 30 mins. Its terrible, bad design fault

I have the same problem with my Toshiba G900 (WVGA too). Very slow on USB, but normal fast at standard charging or car charging. USB is very bad for this at all.

it really depends on what you're doing with the phone, its unlikely to charge when busy, its a lot faster at charging than my old advantage, im actually impressed!
have you made sure that you've not ticked turn off charging whilst connected to a computer?
charged in under 3hours whilst on connected to ubuntu yesterday.

don't u guys realized how many amperes that a USB socket and your PC (as well as the power supply) allowed compared to a wall socket?

usb chargin usually is never worth it.

I don't understand your disappointment, usb voltage/ampere are the same for all devices, even for my touch when used as modem doesn't supply enough power for charging seriously

Does it even charge at all via USB when the X1 is on idle? If it does, how long does it take from low to full?

I left my X1 idle on USB for 6 hours, it was nearly flat when I put it on and after 6 hours it was still 1 bar below full. Whereas my LG Viewty fully charged in about 2 hours. My Universal only takes about 3 hours
So in my case, comparing the three phones, you can see where my dissapointment originates from.

vinokirk said:
I left my X1 idle on USB for 6 hours, it was nearly flat when I put it on and after 6 hours it was still 1 bar below full. Whereas my LG Viewty fully charged in about 2 hours. My Universal only takes about 3 hours
So in my case, comparing the three phones, you can see where my dissapointment originates from.
Click to expand...
Click to collapse
But remember the size of battery the x1 has maybe the 1500 comes into play.

BuddyLee said:
But remember the size of battery the x1 has maybe the 1500 comes into play.
Click to expand...
Click to collapse
Well, of course. Xperia's battery is bigger. That's like complaining that your glass fills up faster than your pool. (may be exaggerating a bit )

BuddyLee said:
But remember the size of battery the x1 has maybe the 1500 comes into play.
Click to expand...
Click to collapse
True tho, point taken.....dissapointment level aleviating.....slightly....

After my phone beeped saying the battery was low, I plugged it into my USB hub (which has a mains supply). An hour later I removed the cable and the phone beeped again.
At least with my P990 I was able to gain some charge, it seems like with the X1 it just stops the battery running down.

Try it after Softreset again. I had this problems with an old ROM on my G900 too. After some time it did not charge. Softreset fixed it.

also yall are forgettin that it's a different kinda battery in the x1 compared to other phones it's ising a li-po compared to a li-ion (which is in most other ppc phones) it charges slower via usb because it's tryin to keep from exploding any extra surge that the usb gets could cause your phone to explain
the li-po is more likely to explain given the way it's built
when you use the wall chargers and car chargers the connection are ment fron rapid rechargin of the device unlike the usb which is for data transfer mainly
when you think about the charge time just think about how long it actually takes for your phone to run out of battery life from what i heard it's close to like 1.5 to 2.5 days compared to normal ppc phones that last probably a day at the most with out recharge
hope this help

Keland44 said:
also yall are forgettin that it's a different kinda battery in the x1 compared to other phones it's ising a li-po compared to a li-ion (which is in most other ppc phones) it charges slower via usb because it's tryin to keep from exploding any extra surge that the usb gets could cause your phone to explain
the li-po is more likely to explain given the way it's built
when you use the wall chargers and car chargers the connection are ment fron rapid rechargin of the device unlike the usb which is for data transfer mainly
when you think about the charge time just think about how long it actually takes for your phone to run out of battery life from what i heard it's close to like 1.5 to 2.5 days compared to normal ppc phones that last probably a day at the most with out recharge
hope this help
Click to expand...
Click to collapse
Err... this is not true for TP. TP lasts about 2 days on average from normal daily usage and it doesn't have problem charging via USB. Given that the port used is USB 2.0 not 1.1 or below. Took about 2~3 hours from nearly flat to full charge if I remember correctly. I have to try again just to make sure. But definitely not taking 6 hours.
I would've thought that X1 shouldn't have any problem with charging since the battery is only like 150mA more than TP. Also, if it's charging faster from the AC adapter, the same result should be expected when charging from USB port. Doesn't matter the type of battery used. Unless if X1 somehow limits the charging current on purpose when PC USB port is detected. Even though USB 2.0 is actually capable of giving out 1.5A maximum. Try to soft reset it after charging for about 2~3 hours. See if the battery gets fully charged. Some TP users are experiencing this issue as well when the battery meter only updates to fully charged after doing soft reset. Experienced users might want to try and measure the current drawn when charging via USB 2.0 port.
Hope this helps.

On my xperia if i put it in sleep mode, it charges no problem using USB.

the advantage used to charge slower from a usb port, that is until someone found out that the standard ac charger had a short across two of the usb pins, and with a quick mod of a usb cable charged quickly from the usb on a computer
however my x1 charges the same from usb or mains, I use the same cable, but can't see what difference that makes.
there are three conditions that affect charging speeds, whether device is on or not, off charges much faster, whether screen is on or not, screen off charges faster, whether theres good radio signal, if like at home, reception is dodgy it can really draw a lot of juice.

Just for comparison sake, I did a test on my TP just to confirm. Charging via USB 2.0 while it was on idle with screen turned on, from 4% to 100% it took about 2.5 hours and its battery feels warm.

Ok lets clear out some things.
A standard PC USB socket can provide maximum 500mA (milli-Amperes) Current at 5 Volt. Ideally that means that a battery rated at 1500mAh (milli-Amperes-hour) can be charged around 3 hours (minimum). Now, subtract the current that the xperia needs while operating and you will get how many milli-Amperes are left for charging.
Of course in order to know how many current the xperia needs to operate you need to connect an ammeter in series, also keep in mind that current needs change depending on usage (wifi, 3g, bluetooth etc).
So in essence if you USB port is not very good and can't give fully 500mA and the xperia needs a great amount of current to be on, then the charging time can be quite long. A simple formula could be:
xperia_Battery_mAh / (USB_Current - xperia_Current)
Now the mains charger is rated at a greater value than the USBs 500mA. Actually I don't own yet an xperia (waiting patiently to arrive), so I don't know how much current the charger can give. Can someone see what is the rating of the charger?
From other devices I own (that can charge through USB) I've seen that their chargers are rated as high as 2 Amperes. Obviously these devices never draw so much current, it is just a failsafe or it was more cheap for them to bundle a charger like that. But they could draw 800mA of current which the USB port is unable to do so.
Keep in mind that while charging with USB might be longer, generally it can be safer for the battery (longer battery life and more charge/discharge cycles), although I am not so sure about this with excessive charging times in a USB port.

Quick question about charging a mobile battery

Quick question. If you leave your phone plugged in and its fully charged and your using it, is the phone just leeching off the charger for power or is the charger pushing out small bursts of power to the battery. The context of my question is i'm starting to use webtop alot and I leave my phone on all day plugged in. Is continuing this behavior going to impact my battery or does the phone just leech directly off the charger without using the battery?

It's fine to leave it plugged in all the time. The phone has a "smart circuit" that use what is called trickle charge to just continually top off the battery as it drops below full charge. The phone is designed such that it doesn't receive power directly from the charger or USB cable, unless the +5v DC current is on pin 1 like a factory flash cable.
Bottom line is there is no damage or shortening of the life of the battery to leave it charging all the time while in the dock or any other means and Li Ion batteries no not have memory problems.

On a related note, is there any damage in using low-power chargers?
I have an external solar-powered battery charger that also supports USB-out, and I find that it doesn't put out enough power to really charge the battery, but it can keep the battery at its current charge level (whenever it is plugged in) for the equivalent of one charge (so the phone could theoretically last 2ish days).
I'm wondering whether this is constantly charging/discharging the battery (bad thing), or just providing enough power to run the phone (good thing).
I've also seen a similar behavior when charging over USB. If I'm using the phone a lot, sometimes a usb port doesn't supply enough juice to charge the phone.
I also saw this in some (rarer) cases with my OG Droid, but I didn't pay it much mind because I had 3 batteries for that thing and you could pick them up for a few dollars off of Amazon.com.

Thanks!
cellzealot said:
It's fine to leave it plugged in all the time. The phone has a "smart circuit" that use what is called trickle charge to just continually top off the battery as it drops below full charge. The phone is designed such that it doesn't receive power directly from the charger or USB cable, unless the +5v DC current is on pin 1 like a factory flash cable.
Bottom line is there is no damage or shortening of the life of the battery to leave it charging all the time while in the dock or any other means and Li Ion batteries no not have memory problems.
Click to expand...
Click to collapse
Thank you so much for your response. I had a feeling it was something like this. Good old "smart circuit".

podspi said:
On a related note, is there any damage in using low-power chargers?
I have an external solar-powered battery charger that also supports USB-out, and I find that it doesn't put out enough power to really charge the battery, but it can keep the battery at its current charge level (whenever it is plugged in) for the equivalent of one charge (so the phone could theoretically last 2ish days).
I'm wondering whether this is constantly charging/discharging the battery (bad thing), or just providing enough power to run the phone (good thing).
I've also seen a similar behavior when charging over USB. If I'm using the phone a lot, sometimes a usb port doesn't supply enough juice to charge the phone.
I also saw this in some (rarer) cases with my OG Droid, but I didn't pay it much mind because I had 3 batteries for that thing and you could pick them up for a few dollars off of Amazon.com.
Click to expand...
Click to collapse
To my knowledge, there is no reason a low power charger should present any problem, but charging from the USB on a PC is limited to 350mA and will definitely not push enough current to charge the phone while it is under heavy use like Mobile Hotspot tethering with LTE or even 3g.
The standard wall charger is 850mA and even that can sometimes only keep up or charge very slowly under heavy load.

USB spec is [email protected] not 350mA. But yes, a dedicated charger probably will charge faster. Some may go as high as 1A output...
Sent from my DROID4 using Tapatalk

Want faster charging/Device discharging while charging/not charging? Read within!

Background
Hi all, I, for a very short period of time was suffering from the problem of my phone DISCHARGING while it was charging. This made no logical sense to me until I did some research, which I will detail below.
How USB Power works (Roughly)
Firstly let's discuss USB power provisioning. Strictly speaking, the specifications say that any given USB port should provide a maximum of 500mA (or 0.5A) at 5 volts. *Don't shoot me electronics guys, I'm simplifying for ease of explanations sake*. Imagine that ampage as the actual force of the charger, how quickly it can ram power into your phone. Like the rate of flow on a pipe.
The beginning of the problem
This was all fine and dandy when all USB was really used for was Keyboards, Mice, Memory, etc, low current draw devices. Something else I should mention here is that the Ampage that a port CAN provide is not the Ampage it DOES provide - the device draws a certain Ampage and if the USB controller agrees it outputs said Ampage. Later, when USB was beginning to be used for more power hungry applications, ie External hard drives, these required more power than the port could (In theory) provide. However, most more modern motherboards/USB controllers were more than capable of supplying plenty more Ampage if it was requested. This was breaking the specification but not in any massively dangerous way so as such nothing bad happens.
This is where we get to the actual issue people are experiencing here. The Nexus 4 is a standards compliant device in the respect that it seems to only draw 500mA from any USB port no matter what it's potential, unless it's an AC Wall wart. If you're experiencing problems with wakelocks (see XDA) and other things, this causes your phone to draw more than 500mA which means your phone actually discharges while it's charging! Terrible!
This is quite easy to get around, but again I'm going into detail so let's explain how the phone tells the difference between a dumb wall wart and a USB controller. Easily! The USB controller obviously makes use of the data pins found within the USB cable, whereas a wallwart just (almost always) shorts them out. The Nexus 4 can detect this short, and as such draw more power *While still in quotation marks staying in spec*.
The root problem is not with how the N4 is charging, it's with the wakelock you're experiencing which is causing the phone to draw so much power while the screen is off. While the screen is off and the phone is in Deepsleep (A CPU state where it uses very little power) - it should draw no more than 50mA leaving 450mA for charging the battery, but you guys are probably experiencing a wakelock of some sort.
Solutions to the problem or How to break a specification for the good of mankind
The simple solution is to install this app: https://play.google.com/store/apps/details?id=com.rootuninstaller.batrsaver
This forces the device into a Deep sleep when the screen goes off by killing applications and turning off all internal chipsets that have wakelock capability, most commonly networking on the Nexus 4. This will allow your phone to charge (slowly) off USB without an issue. Another common wakelock is when the device is picked up by your desktop as a media device. The USB controller inside the Nexus 4 forces a wakelock which keeps it from charging. Stupid design, I know.
* A more hackish solution is to install Francos kernel, buy his app, and tick the Fast charging option in the kernel settings dialog. This will force the phone to think that everything is an AC adaptor and will force the phone to draw as much current as it can from the USB port (which on most modern motherboards is fine, and results in extremely quick charging).
* An even simpler solution than all this is to just use a 'USB Charging cable' - this is simply a cable that does not have the Data pins, and as such does exactly the same as what enabling USB fast charge above does. http://www.ebay.co.uk/itm/Micro-USB...487076?pt=PDA_Accessories&hash=item51a465d124
If you live near a Poundland store here in the UK they sell a 4 in one USB cable type thing which turns 1 USB port into Ipod sync connector, Nokia connector, MicroUSB and MiniUSB, and this doesn't have the data pins and as such is excellent.
One final point, an excellent app for monitoring whether your device is actually charging or not and how quickly is Current widget: https://play.google.com/store/apps/details?id=com.manor.currentwidget&hl=en
This widget will tell you how much Ampage is going into or leaving your battery. If the battery icon is green, then it's discharging, if it's black/white then it's charging. The bigger the number, the faster the discharge/charge. This is an extremely easy way to test speed of chargers too.
Recommendations
Another solution, just use an AC Wall wart - they're cheap as hell and the one supplied with the Nexus 4 is an extremely fast charging one. Shame I've gone and lost mine.
A way to roughly monitor charging current draw
I'd also recommend you install https://play.google.com/store/apps/details?id=com.manor.currentwidget&hl=en and monitor, if the battery is green while charging it's discharging and you need a more powerful charger/to figure out what's causing your phone to use so much power.
General good values in Current Widget
I generally saw a max draw of about 750mA for charging (not including draw for powering the device, the Nexus 4 can draw more power to charge and power the device) on my old Rev10 first generation Nexus 4. On my new Rev12 board I'm noticing this increase to about 850mA.
Are higher amperage chargers any benefit to anyone?
Yes and no. You will not notice faster charging unless you use your device while charging. Your nexus will draw as much power as it needs to power the phone while charging at the fastest rate. For example on the stock 1.2a charger
1200mA | 800mA goes to charging 400mA goes to powering the phone idling
Let's say you start a stability test. Your phone will obviously be using a lot more power so this will happen
1200mA | -600mA goes to charging and 1800mA goes to powering the phone stability testing
That minus value above may look strange! Let me explain. If the phone needs more power than the charger can supply, it will draw from the battery. That's the minus number.
If you have a higher ampage charger like for example a 2.5a charger
2500mA | 800mA goes to charging 400mA goes to powering the device
Stability testing
2500mA | 700mA goes to charging 1800mA goes to powering the device
Can you see the difference?
DISCLAIMER: I am not an electronics engineer nor do I claim to be, I am simply a hobbyist and this is what I've found to be the case. Please correct me if I've made any mistakes, I want to learn.

Thanks!
Thanks so much for this post. It's very helpful.

kn100 said:
Another common wakelock is when the device is picked up by your desktop as a media device. The USB controller inside the Nexus 4 forces a wakelock which keeps it from charging. Stupid design, I know.
Click to expand...
Click to collapse
This isn't true for everyone then as mine connects and charges just fine off of my laptop and desktop when connected as a media device. In fact its on my laptop right now charging, gone from 68% to 81% in about 30 minutes and it shows connected as a portable media player.

Great info! Thanks for writing this!
In certain use cases the Nexus4 discharges faster than it charges and this is a very useful guide.
I use my phone for navigation in my car and having the GPS on and the screen at high brightness
drains the battery faster than the 0.5A car chargers can supply. Car chargers rated for 2.0A work well.
I haven't tried a 'USB charging cable' with the data pins shorted, it may work as well.

-Mindroid- said:
Great info! Thanks for writing this!
In certain use cases the Nexus4 discharges faster than it charges and this is a very useful guide.
I use my phone for navigation in my car and having the GPS on and the screen at high brightness
drains the battery faster than the 0.5A car chargers can supply. Car chargers rated for 2.0A work well.
I haven't tried a 'USB charging cable' with the data pins shorted, it may work as well.
Click to expand...
Click to collapse
was over in Nexus 7 forums and the 4.2.x kernel should have solved the problem at least for having to use shorted cables. have to wait and see if 4.2.2 brings any more changes.
http://forum.xda-developers.com/showthread.php?t=1984838
Section 6 in this link is about power supplied through USB
http://en.wikipedia.org/wiki/Universal_Serial_Bus
I can't tell if we have an updated kernel allowing faster usb charging as I'm limited by the power output of the usb port in my laptop. The output (5V at 500mA max) is controlled by the laptop (USB Standards) and it doesn't matter what the phone or cable is capable of as that's the max it will give out and that's about what I'm charging at. If I had a dedicated charging port in my laptop then it would be different and I could see if its able to draw more power. I have a 1.0 amp port in my car and it does charge at the higher amperage, I would assume it would do the same thing if I had a 2 amp usb port in the car. So I think the stock kernel has the fast usb charge built in it just depends upon if you have a usb port capable of providing a faster charger, it has nothing to do with the cable as I'm using a standard unmodified micro usb cable and its able to draw the max a usb device is able to put out.

thanks
thanks for a great detailed post!!!
I have the same trouble with my N4 when I was charging while using my phone...
I find it very slow... I guess I've been spoiled by my previous iPhone (which charges fairly fast)....
i might be stating the obvious but I find the phone charged "a lot" faster when it's OFF
if you are running low with your battery and need a quick 10 min charge, just do yourself a favour by turning off your phone...
the difference is quite significant!

kzoodroid said:
This isn't true for everyone then as mine connects and charges just fine off of my laptop and desktop when connected as a media device. In fact its on my laptop right now charging, gone from 68% to 81% in about 30 minutes and it shows connected as a portable media player.
Click to expand...
Click to collapse
Yup, me too. It only discharges while charging when I am playing like NFS most wanted.
Sent from my Nexus 4 using xda app-developers app

The issue with cables is with the LG usb wall charger as the one supplied isn't capable of getting the 5 volts at 1.2 amps that the charger is rated at, mine is getting around 300 - 400 mA. The micro usb cable I have in my car and use with my laptop (for charging and data transfer) is able to handle the higher amperage, it gets around 1 amp with the LG plug. There are no specs on these cables so I can't list a definitive difference and I would assume that the cable mod in the OP might help with the LG cable. It also might just be simpler to only buy those cables capable of handling higher amperage as obviously they are out there from my experience.

The cable I'm using is an RCA coiled charging/syncing cable model AH732CBR (has data pins). The maximum I'm getting from this is about 870 mA regardless of the amperage of the usb port, I've tried a 1.0, 1.2 and 2.1 and they are all around 870 mA on current widget. I would suppose if I could find a strictly charging cable I could get higher (link to ebay in OP is outdated) but this is still 2x that which I'm getting from the LG cable supplied with the phone which only puts out 300-400 mA. Our phone also has Qualcomm's quick charge which is supposed to improve battery charging times by 40%.
http://www.droid-life.com/2013/02/1...allows-your-device-to-charge-up-to-40-faster/

How do you measure how much mA the device draw from the charger?
Sent from my Nexus 4 using Tapatalk 2

omrij said:
How do you measure how much mA the device draw from the charger?
Sent from my Nexus 4 using Tapatalk 2
Click to expand...
Click to collapse
current widget, link is in the OP

kzoodroid said:
The cable I'm using is an RCA coiled charging/syncing cable model AH732CBR (has data pins). The maximum I'm getting from this is about 870 mA regardless of the amperage of the usb port, I've tried a 1.0, 1.2 and 2.1 and they are all around 870 mA on current widget. I would suppose if I could find a strictly charging cable I could get higher (link to ebay in OP is outdated) but this is still 2x that which I'm getting from the LG cable supplied with the phone which only puts out 300-400 mA. Our phone also has Qualcomm's quick charge which is supposed to improve battery charging times by 40%.
http://www.droid-life.com/2013/02/1...allows-your-device-to-charge-up-to-40-faster/
Click to expand...
Click to collapse
Bit of a late reply but please bear in mind the Nexus will NOT draw anything more than about 800mAh from the wall for charging alone. That is the absolute max and is a hardware limit - If the cable is transmitting that and it's showing in current widget you've got a good setup. See the added section in OP for more info on higher amperage chargers.