I also want to share my experience with repairing the microphone.
From one day to the next my microphone didn’t want to work anymore. This was not the first time but now, I can’t buy a new bottom module…
I read a few times that the pcb tracks are maybe cracked. So I opend my bottom module, heated it up to soften the glue and the solder and removed the microphone from the pcb. And the result was: All three tracks are broken (now) (see picture below)…
The solderpads of the pcb were still on the bottom side of the microphone. And as you can see, there is a short between two of the four contacts. After cleaning up and solder removing, you can see in the green pcb of the microphone, there is already a short between these two contacts. Therefore, the microphone need only 3 contacts to the board.
I scratched away the black of the three remaining tracks so that you can see the copper and you have new contactpads for soldering. The microphone contacts got new solder (a little bit too much) und flux so that there is enough which can flow to the new contactpads. I put the microphone back on the pcb, a little bit displaced so that the solder is over the new pads, heated it up and pressed it to the board.
How did you do that? My FP2’s microphone does not work any more. There is no waranty left, so, having not much to lose, I would like to try to repair it like you.
Currently, I’m at this point.
I don’t know how to go further.
I don’t manage to take the circuit out of its case.
Won’t I break it?
How did you do?
As you can see on my pictures I didn’t take the PCB out of its white case. But with the heat you will probably attack the case and melt it a little bit. When you are careful, a little bit of melting won’t be a problem, but you need a hot air piston so that the hot air will hit only the microphone. Otherwise I recommend to separate the PCB from the case.
Thanks for your reply.
I was impatient, I had no hot air piston, so I put the PCB and the half case in my oven.
It melt, and, as I was not careful, it melt more than few.
Well this half of case is not usable any more now, but I was able to take off the microphone.
The phone is still usable with only half a case for the bottom module and no primary mic.
I’ll try to solder the microphone some day soon.
Thanks for sharing your experience with repairing the microphone @unhawkable! I had almost missed this post of yours since the thread is about repairing the µUSB port, perhaps one of the kind mods could split the topic and title it appropriately?
I’m currently facing a similar issue with the microphone not working while the rest of the bottom module continues to function. I’m hoping it’s not the traces on the board that have cracked, that it’s only the solder on the surface mount that has cracked which can be fixed by melting it with the heat gun and letting it cool again, doing a reflow of sorts.
Are there any gotchas I should be aware of before attempting this? I assume it’s better to loosen the glue with the heat gun and remove the board from the plastic casing to avoid melting it. Did you heat up the whole board or just the area around the microphone? What temperature did you heat it up to, did it not damage the mic? (I would’ve assumed excessive heat would’ve damaged the coil found in a dynamic mic, but the FP2 may be using a piezo mic or even something completely different; is the type of mic used here known?)
I’ll be sure to report back with the results. In the (fairly likely) case that I fail, I’m already looking around for a replacement module anyway - the only reason I’m even attempting this is because they’re no longer available from the web shop.