Redmi 2 Prime (2014811) no signal (hw fault)

[-=Guybrush=-]

Hello to everyone. I've a motherboard from a Redmi 2 Prime 2/16Gb (2014811) which works fine but gets no signal. SIM cards are recognized but I get no service. I'd like to point out that baseband, IMEI and IMEI SV are fine and I've also restored a fresh qcn, everything to no avail so the problem is definitively hardware. As you can see here



the metal shield for what I believe is indeed the RF circuit according to the schematics has been removed (I've bought the motherboard AS IS) and is missing. I suppose it has been removed to replace one of the resistors and capacitors or most probably the QFE2101 IC (there aren't other components there).
Could the problem I'm experiencing be related to the QFE2101 IC only (maybe it has been poorly replaced or replaced with a defective one) or could it be triggered by the missing shield? Could it be the latter, I was thinking to solder a thin wire connecting all the solder pads on the perimeter to restore the contact between them but I don't think it would help.
Please note that the sign which seems an oxidation sign isn't that but just a reflection: the board seems definitively not water (or moisture) damaged.
I attach a screenshot to better detail the situation:



(I've tried to change the preferred network type too to no avail). Thanks in advance for your advices and have a good day!

[-=Guybrush=-]

No advices at all? Do you need more details? I'm free to give them if necessary...

[MVNDOzone]

first flash modem
redmi 2 have 2 modem file

[-=Guybrush=-]

Thanks for your advice but unfortunately this isn't the case. I know that and the proper modem is already installed. To be more precise, there are four modems: one for each version (wt88047/2014811 and wt86047/2014813) and for the same version there are two flavours (one for Kitkat and the other for Lollipop). I know all of that and the proper modem is definitively installed. I've already ruled out a software issue: unfortunately, it's definitively an hardware one.
Given that here there are members much more skilled than me, my question is if the missing shield could make a difference (I don't think so but, should this be the case, my question is if my suggested workaround could help) or where I'm supposed to look to try to fix this motherboard.
Thanks again!

[pazeth™]

no its not hardware..........................

[-=Guybrush=-]

What then if not hardware? As already explained, I'm sure many of you have much greater knoledge than me but making a statement like yours without explaining doesn't solve anything.
Just to outline the situation even better, I've also wiped modemst1, modemst2 and fsg. I've done everything that could be done software wise. The only thing I haven't done (because I haven't another 2014811) has been making a full backup by TWRP from a working mobile and restoring it to the broken phone (I know that later on it's necessary to change IMEI, serial etc. but this isn't an issue): this should definitively rule out any software issue though I'm confident all the attempts I've done (documenting myself before, not shooting in the dark) should already.
Again, I'm free to make verifications or whatever is necessary but I need to be given a path to follow. I can be well wrong but I'd like you to tell me why. Thanks in advance!

[-=Guybrush=-]

I'd like to underline just another thing: I've a lot to learn and I'm here asking exactly for that reason. I don't think I've all the answers and I don't want that message to pass.

- EDIT -

What about those strange values for signal strength for example? By what I know 255 ASU is a 'non-value' to tell a value can't be determined... Also, I haven't the tools (I guess an hot air station) to remove that shield on the RF part so I imagine a professional has done it: was he so dumb to do it without the need to? Everything is possible but I don't know...

[-=Guybrush=-]

No advices from anyone? Some of you seem to know where the problem lies but then I ask to myself: "is it some kind of secret? Why no one wants to give me an hand?"

[-=Guybrush=-]

I've undestood unfortunately: this forum is aimed to professional repairers and someone who like me is out of the 'caste' wouln't ever be able to receive any kind of help. This is very disappointing and against the funding principle of a forum I believe but, given that the situation is this one, is there someone in Europe willing to do the repair for me at a reasonable price?
I'd like to solve it by myself to spare something (the mobile is old and isn't worth a lot) but first of all to learn but this woulnd't ever be the case unfortunately. It's a pity!