Then I might bet the mortgage payment it is the FireFly panel causing the issue.
- If shore power is present or generator is running, shut off the breaker to the Converter. If you are not on shore power or generator power, you can skip this step.
- Put the Use / Store switch in the "Store" position so there is no 12V power in the coach. The FireFly panel should be off / blank and not light up when you touch the screen.
- After waiting 30 seconds, put the Use / Store switch back to the "Use" position to restore 12v power.
- Start the generator and then try the back A/C unit. If you turned off the Converter breaker, be sure to switch it back on.
When I have had intermittent A/C control issues, rebooting the FireFly panel has corrected it every time..... at least temporarily.
If your rear A/C starts working, it is the FireFly panel causing the issue. You should then check your firmware version of the G7 panel. You should be running firmware v6.14. The version is found in the diagnostics section of the panel. If you are on and older version and it is not 6.14, you should contact the dealer about a firmware upgrade.
I have v6.14 but I am scheduled with the dealer to have my main G7 board replaced after doing some troubleshooting directly with FireFly.