Boss FBM-1 Bassman help please?

[Fuzzlefty77]

Just got my hands on a faulty Boss FBM-1 Bassman pedal. Initially the pedal powers on fine with mains power and LED on/off works fine with footswitch. Then LED just stays on all the time and pedal gets hot and a bit smelly very quickly.

Power supply double checked and is good.

Using a battery the LED is really dim and eventually doesn't show at all. Its a new battery.

Nothing seems too crispy or untoward inside the pedal.

Any ideas? Can post gut shots if required.

Teeny tiny surface mount stuff so not really sure what I can check on this.......

Thanks,

[plush]

Getting hot - means a short / component failure. You can locate what is getting short pouring some IPA over the working board.
Dead shorts can be located with a dmm. Using lab PSU with current limiting will help not to destroy your pedal.

Post guts.

[Fuzzlefty77]

Best gut shots I can get without fully disassembling:

[plush]

Best gut shots I can get without fully disassembling:

Ok, now you should look for what's getting hot. Also pls check Q17 pins, looks like a cold joint on pin 5.
Do also check other ICs for visual damages - cracks or small holes like this