Generator transfer switch cutting out

I am having an issue when running our generator.

Periodically, for no apparent reason, I will hear the transfer switch cut out, and in turn, all AC loads stop functioning. A short while later, ~15 seconds, it switches back again, and the AC power is restored.

I see two reasons. Either the generator is losing output power for some reason, and in turn, the switch is cutting out, or the switch has an issue, and needs some TLC. I figure the best place to test things would be at the switch and see if power is actually dropping off the generator, or the switch is malfunctioning.

The switch is behind the AC breaker box as best I can tell from the noise.

It seems the bulkhead wall that the breaker box is affixed to can be removed, however I do not see anything in the service manual about accessing the transfer switch.

Anyone encountered an issue like this, or gained access the the transfer switch to take a look?

As the Onan generator and thus presumably the transfer switch were added by Airstream, the various manuals would not mention.

There may be some folks who may have fooled around with the transfer switch if they removed the generator.

I think you're right re the transfer switch being behind the AC Circuit breakers. When I firsr got the Westy, it looked like people had fooled around in that area.

Please posts photos and info on whatever you find. Thanks.

Note: What is an automatic transfer switch? https://www.rvtechmag.com/electrical/chapter4.php

Note: Others things checked first: https://roadtreking.com/help-generator-runs-dont-power/

Note: Switches for sale (no luck seearching for Airstream and transfer switch).

https://www.pplmotorhomes.com/parts...er-switches/automatic-transfer-switch_55-8933

https://www.pplmotorhomes.com/parts...cal-systems-and-accessories/transfer-switches