Ubiquiti UAP-AC-M-PRO No Power on

[Hasoobi]

Master's Help Required Ubiquiti UAP-AC-M-PRO No Power Power Over Ethernet PD Interface and PWM Controller IC : LM5072MH-80

[stj]

Q10 is not soldered

[Hasoobi]

Yes Desoldering For Test Mosfet Ok

[ant3202]

had you check the diodes for any shorts?

[Hasoobi]

not found any short or change value

[dizzyadam]

Last time I had something similar with an AC-PRO, spent hours why there was no any voltage flowing. I nearly gave up and just tried to dump the SPI/BIOS for future use. Turns out to be corrupted. Flashed a copy of bios from a spare AC-PRO and was working fine again.

[Hasoobi]

do you have Bios dump ..?

[dizzyadam]

First of all, measure voltage across the bridge rectifiers and see if you get 48V going into LM5072. Have you checked any shorts on the LM5072 itself - if so, take it off and checked for shorts around it and see if it still persists. Had a bad LM5072 on my previous fix on a different U6-LR - replacing fixed it.

If you're not getting any voltage from the 3.3V/5V from the UART pins then it's probably a bad LM5072 (or something else) and not the bios.

If you want to go ahead with SPI dump route, I suggest you create a (verified) full backup of your current SPI/BIOS dump (upload it here). What I've attached is for the UAP-AC-PRO (not the AC-M-PRO) so it's not going to work correctly or might not even work at all (Most likely will get Error A12 if you get in but it has different ethernet hardware) but you might be able to at least confirm that power works then find someone with a AC-M-PRO to get their SPI dump.