Receiver turns on, but turns off after a couple of seconds.

what brand/model? Most likely there is a short in the amp that will need to be repaired

This happens because of internal overheating - clean the air vents and if you have covered the receiver with a cloth please remove the cloth your problem could be resolved

Thermocouple may need replacement.

Throw on a couple of shrimp it and let us know when they're ready. You need a pro to look inside it.

There is a problem in the front end that is allowing some DC curent to flow to the output section. This is detected and the amp goes into protect mode to prevent further damage to either the output section or the speakers. This is likely to be defective coupling capacitors and not an expensive repair. Figure on less than $20 for parts for this repair.

Dan

You may have to ( first unplug it from the wall) then pull the top case.
Locate the tuner board , it will be the one with the antenna connections sticking out the rear of the rec'r.
If there's some way to pull the circuit board up and out of a socket/sockets , try that and re-install it.

Other than that I may be able to help you find a good tech.

Make sure that your speaker wires are not touching and setting off the fuse. 

When you turn on receiver it will power off. Poweroff shows up and than turns off. if the front panal reads over load the output ic pac001a is defective i had repaired this model before

I'm having the same problem with my AVR 435. Did anyone ever figure out how to fix this?