Memphis MC1000D relay doesn't click

[ComputerJLT]

the amp works, all the waveforms are good on the power supply and outputs, nothings burnt or caps blown. current is normal in idle and playing.

I even get audio; but i have to manually click the contactor in the output relay...

Where should i start looking? psu driver card? caps/resistors/transistors near the output relay?

I've already metered the pins on the relay coil and voltage doesn't change when the amp powers on. one odd thing to note is that the power/protect light bounce back and forth about 3x before the power light stays green.

 

[timwebb]

u might have a slight short. there is a diode near the relay that engages it.

 

[ComputerJLT]

slight short where?

 

[timwebb]

i had one with the same issue it was the windings coming from transformer wire touching inside.

 

[ComputerJLT]

c91 may have vented; tehres little fibers on the board near it but it still reads 25uf on my meter; i have another 22uf electrolytic i can use but its polarity is not labeled. can anyone tell me the value of c91

 

[timwebb]

u got a picture?

 

[Perry Babin]

Where is it on the board?

 

[ComputerJLT]

c91 is near the led's. id post a pic but the amps not near me. its near the big 12v filter caps and the big power supply torroidal trafo

 

[ComputerJLT]

i pulled the cap last night and tested it, it tested good out of circuit.

I'm starting to think the issue may have something to do with the two transistors that are connected to the muting relay. the 2 transistors look like they switch to ground when the amp comes up and goes out of protect; one was reading in circuit like it was bad but i didnt pull it to test out of circuit. i'll do that next. i dont have the location on the board of the 2transistors but they're connected to the relay and on the leg thats not connected to +12v battery input