I have five Optimus L90 D415 phones for my family. My phone quit working on the T-Mobile network, although the wi-fi connection still worked for Internet usage only. No calls or texts could be sent or received, even with wi-fi calling enabled. The signal strength indicator was missing from the display. In Settings>About Phone>Network, Network was unknown, signal strength was zero, Service state was "out of service", and Mobile Network state was "Disconnected". In Settings>About Phone>Status, my phone number was unknown, IMEI was unknown, and IMEI software version was unknown.
T-Mobile said I needed a new SIM card. Got one, no help. That was the best they could do. After that, they said I needed a new phone, despite this one being only a few months old with no damage.
I took one of the other phones that was no longer in use, but still worked. The only fault was a cracked screen. First thing I did was to swap out the motherboard. This did not help, the fault stayed with the phone. Next, I swapped out the antenna cable that delivered cellular signal to the motherboard. No help. Finally, I swapped out the charger dock flex board. This board is on the other end of the antenna cable. This fixed the problem. This board does nothing more for the signal than provide a connection for the cellular antenna built into the rear frame, but there are also some very small components on the board (probably 3 caps and an inductor) mounted in the antenna circuit. My guess is that one or more of the caps went defective.
The charger dock board for the D410 and D415 is available on eBay for about $6. It is easy to replace. Find a disassembly video on YouTube, and remove only the silver rear frame, which exposes the motherboard and the charger dock board. Disconnect three connectors used by the charger dock board (two on the right, one of which is the antenna cable, and one in the center), then use a flat pry tool to remove it. Slide the pry tool underneath the antenna connector, and wiggle it back and forth to loosen the adhesive that holds the board in place. Once that side of the board is loose, slide the pry tool underneath the dock connector, and work the center of the board loose. Next, work the pry tool toward the opposite edge. Remove the defective board, and replace with a new part.
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Hi All,
A couple of weeks ago while repairing the cracked screen of my HTC One I broke the Wi-Fi/Bluetooth cable running across the phone. I ordered a new one and used the phone without it (With very poor Wi-Fi range) until the new one arrived. The antenna arrived yesterday and I installed it in the phone, however, upon booting the phone I have found that the range is still very poor.
Someone please help!!!
Thanks,
NoBones
NoBones said:
Hi All,
A couple of weeks ago while repairing the cracked screen of my HTC One I broke the Wi-Fi/Bluetooth cable running across the phone. I ordered a new one and used the phone without it (With very poor Wi-Fi range) until the new one arrived. The antenna arrived yesterday and I installed it in the phone, however, upon booting the phone I have found that the range is still very poor.
Someone please help!!!
Thanks,
NoBones
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Click to collapse
You might have damaged your wifi/bluetooth transmitter/receiver by using it without the antenna connected. Transmitters are designed to work with antennas that have calculated length and impedance based on the wavelength (frequency) used. If not using the right antenna or no antenna, most of the power is reflected back to the Tx/Rx circuitry and can cause irreversible damage.
Never use a device without its antenna or with the wrong antenna, this apply for all devices that have transmitter circuits. (WiFi routers, phones, CB radios, etc etc).
I will not explain in details how it works, if you want to read more about this, search VSWR in google.
Wi-Fi Problem
alray said:
You might have damaged your wifi/bluetooth transmitter/receiver by using it without the antenna connected. Transmitters are designed to work with antennas that have calculated length and impedance based on the wavelength (frequency) used. If not using the right antenna or no antenna, most of the power is reflected back to the Tx/Rx circuitry and can cause irreversible damage.
Never use a device without its antenna or with the wrong antenna, this apply for all devices that have transmitter circuits. (WiFi routers, phones, CB radios, etc etc).
I will not explain in details how it works, if you want to read more about this, search VSWR in google.
Click to expand...
Click to collapse
So how can I get my phone operational again???
I love my HTC :'-(
Probably need a mother board replacement if your issue is caused by what I said
Hello guys,
some days ago I changed the top motherboard (where camera is attached). Since then i couldnt get good wifi connection.
When changing the motherboard, i had the problem that i couldnt stick the wifi cover (as shown in the picture) properly to the new motherboard because I had no new tape. So i sticked it as good as possible and closed the phone.
Now my question: How can I stick the wifi cover properly to the motherboard so I can have good wifi connection. And if it is not possible, where can I buy this wifi cover with tape attached?
Thank you in advance.
might be one of those gold pins in that area. try adjusting some of them and checking that they are making a good connection to the casing.
So I was replacing the screen on my M7 when I realized that I pried off the volume down button. So I had to replace the daughter card on my phone. Well I ordered the sprint specific daughter card and now I've got questions. This phone was purchased through sprint around the release of the M7. My replacement daughter card comes and it is missing two connection points. Both on the left side of the phone (if it's laying face down on the screen). One is a grey antenna cable from the motherboard to daughter board, the other is a black cable from bottom of motherboard to daughter board. I've attached an image showing their locations. Can anyone tell me if these were eliminated after the initial release of the phone? Can anyone speak to what they actually do? I've tested sprint cell signal, wifi signal, gps, and bluetooth so I know none of these are the antenna's not hooked up.
Did anybody notice the two antenna connection points near the SD card? Does anybody know what connector this is? I'd like to buy an adapter to test with an external antenna.
It's called U.FL I assume that one is for the cell radio and the other is for wifi/bluetooth. Does anybody know for sure which is which?
Re: Blu R1 HD Antennas
The coax going from the u.fl near the sim/SD going to the bottom of the phone is the cell antenna. I had to replace my speaker and also upgraded it, requiring me to remove parts of the plastic backing. I didn't see the adhesive antenna and cut through it. My WiFi works great, but almost no cell signal.
Just an fyi here You can get a FM radio to work on blu r1 hd with the unlock tool which can be found here
https://forum.xda-developers.com/r1-hd/how-to/unlock-tool-t3561333
You have to go to the second menu by pressing 5
Hi guys, i bought this phone (used) and there was no issues, but in one day it stops searching wifi. It sometimes may do it, but most time it shows that there is no networks nearby.
I think i should replace wifi module, but found no information where is it on this phone. May somebody told me that?
Hello, I don't think you can change the wifi module : it most likely is a chip soldered on the mainboard, you might want to check the connection between the mainboard and the antenna ?
matmutant said:
Hello, I don't think you can change the wifi module : it most likely is a chip soldered on the mainboard, you might want to check the connection between the mainboard and the antenna ?
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Click to collapse
this might make sense, which antenna should I check?
I don't own the Xperia 10 but it can be either embedded on the chassis with little nipples pressed on contacts on the mainboard (or the over way around) or it could be "standard" U.FL connector. If your device has fallen many times they could be a little loose as these are quite flimsy