TEAC AG 980 going protection mode

[Supradin]

Hi everyone. I'm new on this things, this is my first amplifier after I start offering repair service almost for free, just for learning purpouse

So I have a amp that is going to protection mode. I saw that if I remove the ribbon cable which sends from main board B+,B- and signal for amplifiers card, is not going to protection mode.

So, from that ribbon cable y disconnect everything but b+ b-, and amp goes again to protection mode. So my guess was something is wrong in the amp board.

I disconnect all transistors and amp is ok.
After, I connect the transistors of channel 1...again fail
So I disconnect chanel 1 and connect channel 2...fail again

Another clue could be that only with main board, I have to tap standby button twice. First time, with main capacitors empty, the amp goes to protection mode, but the second time, with capacitors with 60V more or less, the amp stars ok, the voltage rises to 82 in b+b-

Documents here

https://elektrotanya.com/teac_ag-980.../download.html



So....any guess?

[Supradin]

So...i´m going to check this relay... is the only thing that i see which is related with channel 1 and 2...if the coil is burnt...could cause a failure.