Panasonic SA-XR50 (similar to XR70) receiver F76 error

[GnatGoSplat]

I have a Panasonic SA-XR50 A/V receiver that's been in daily use 15-years. Suddenly decided to display F76 error on VFD and shut down. It happens every time I power it on since then, after a random amount of time (seconds to minutes). Seems to function normally until it shuts down. PSU makes occasional faint, but barely audible chirp sounds randomly, not repeatedly. F76 indicates power supply issue. Suspected bad caps, but all caps appear visually normal. All electrolytics on PSU board appear within ESR spec when tested in-circuit.

Anyone come across a similar issue in one of these, or its bigger brother the SA-XR70? Other Panasonic devices (completely different models) with F76 errors seemed to be bad caps, but the capacitor numbers/location/values don't seem to correspond to any in my unit.

Sorry, meant to post in Audio, had another window open in another tab. Mods feel free to move.

[dooder]

Re: Panasonic SA-XR50 (similar to XR70) receiver F76 error

Just curious if you were able to fix your SA-XR50? I have an SA-XR70 with the same problem. All of the capacitors visually look ok, but I'm not sure where to begin troubleshooting.

[GnatGoSplat]

Re: Panasonic SA-XR50 (similar to XR70) receiver F76 error

I did. I pulled off several PSU caps to test out of circuit, and even a few not in the PSU, but they all tested good for ESR and capacitance.

Strangely, I put it back together, and all was fine for many months. Several months later, there has been a couple random times where it got F76 and shut down on its own, but I'd turn it back on and it'd be fine for several more months. It's used daily for several hours a day. I'm leaning towards oxidized contacts in the ribbon cable connectors. If it ever gets worse, I may need to try spraying some deoxit contact cleaner in the connectors.