Kicker zx1000.1 repair question

[TonyK2003]

I have been working on a kicker zx1000.1 amp and seem to have it fixed for the most part I believe. It turns on and everything fine now but I am not getting an output. Thing is though we unplugged and replugged in the rca's and it came on for a second and sounded fine and another time it was a buzzing sound. Any ideas on what to check for that? Thanks for the help in advance.

[Perry Babin]

What parts have you replaced?

What are you using for a signal source?

[TonyK2003]

I have replace most all off the power transistors and the 4 diodes next to the power supply. The source is coming from a deck in the car that is known working before and after trying this amp.

[Perry Babin]

Confirm that the RCA shield ground is intact on the head unit.
RCA Shield Repair

Is the 12v power supply for the head unit the same as the 12v supply for the amp?

If not, is the ground for the head unit's 12v power supply connected to the ground for the amp's 12v power supply?

[TonyK2003]

its all coming from the same source. We took out a good working amp in the car to try this one and it uses all the same connections. The previous amp worked before and after trying the kicker.

[Perry Babin]

The reason I'm asking a lot of signal source problems is because this sounds precisely like an amp that has a problem with the shield ground. If the amp you tried was not the same exact model, it only tells you that the head unit was producing audio.

The reason I wanted you to check the shield ground is because it is a VERY common problem (especially for Pioneer head units). The shield ground in the head unit can be burned in a fraction of a second with no visible evidence that damage was done.

Do you have a test tone CD or a sine wave generator?

If not burn the following to a CD:
http://www.bcae1.com/temp/100hz300seconds.zip

Play the track at ~3/4 volume on the head unit with the amp gain at ~1/2 and the crossover pot set fully clockwise. With one meter probe (doesn't matter which) on the gnd terminal of the preamp board and the other probe on the out terminal of the preamp board, what AC voltage do you read?

Do NOT let the probes slip and short to the power supply pins on the connector (which should read ~±15v DC - you should confirm that you have the proper voltage on these terminals).