Memphis 16-st1000d

[mike49504]

I have another one of theese amp in for repair.

The problem im having is when the board is in the sink the realy makes strange noises and when u try to hook a speaker to it sparks fly out of the output terminals and amp goes into protection.

With the board out of the sink the relay still makes noise but it will produce audio I checked to see if anything was shorted against the sink but cant find anything.

wondering what this might be?

[Perry Babin]

With it in the sink, what do you see on the speaker terminals with your scope (DC, oscillation, clean audio...)?

Did you check for continuity between the heatsink and the tabs of all of the heatsink mounted semiconductors?

[mike49504]

I checked to see if it was shorted from any legs on the semi condutors to the sink didnt find anything but will check again.

I get 25 volts of dc on the outputs for 1 to 2 secs before it is at 0 volts on the outputs

[mike49504]

Perry,

Now it has 52v of Dc on the outputs even out of the heatsink. And the relay squeals also

[Perry Babin]

Does this one have the driver boards that unplug?

[mike49504]

Yes

[Perry Babin]

Are you measuring the DC voltage directly across the speaker terminals?

If so, unplug the audio driver boards that are parallel with the sides of the amp. Do you still have DC on the speaker terminals?

[mike49504]

With both Output driver boards taken out of the amp. The relay kicks on and doesnt squeal and No DC on the outputs. Measuring directly across speaker terminals

[Perry Babin]

Reinstall one driver board at a time to determine if one board is the causing the DC on the outputs.

[mike49504]

I took them out of the board with no power wires hooked up then try to power the amp up without them and have another problem it draws excessive current now and the power supply fets heat up so i have to track that problem down first