Every time I've had issues you describe it's been the start capacitor...Coleman, Dometic and _________! Watch your amps on your voltage monitor (it will happen fast) when the compressor tries to start. The amps will climb then either the whole system will shut down, the compressor won't start or the breaker opens. You probably don't have an inverter type genset, but if so, it will try to carry the load by revving up when the compressor kicks on, then fall back to the pre startup sound. Is the breaker for the rear A/C getting hot? You guys have had lots of lightning recently. Does that t'stat have a battery? I know a repair man in Albuquerque if you want to PM me.
