Repair ZP120

Thanks gruv. Can you tell me what I will be looking for when I short the 2 RTN pins?

The 2 RTN pins are shown in the pic above.

Sorry, I meant assuming no other shorts or issues, should the amp power on if the RTN points are shorted? I should have some time tonight to take a look at it and will report back.

Thanks again gruv2ths for all your help.

No probably not, those 2 points need to be shorted though for the AMP to work right. Light in the front should blink either way. Not sure what would cause the light not to blink with a good working bias converter.

OK so I shorted the RTN pins and no change. Still no power light and the dim bulb tester light came on and then went off. I decided to open the top and have a closer look at the power supply board. That was an adventure 🙂 After finally getting the top off I am stuck trying to figure out how to get the WiFi board off. Daniels guide pointed to the photo stream but that did not provide any help. Any ideas gruv2ths?

EDIT: Never mind, I just found the other hidden screw to the left of the sub woofer analog output. Looking around now....

I need to think about this. This is a new one for me, ad I have never heard of this specific failure.

Thanks gruv2ths. I didn't probe the primary side of the transformer because I wasn't sure what pins to probe and what voltages to expect. Do you know? I also emailed the eBay seller to see if he could provide any information on how it failed and he said he did not know. The amp doesn't appear have been dropped, nor gotten wet or anything like that.

There is 0V across those pins. Since I have never owned a connect amp, can you tell me how long it takes to see any lights after plugging it in?