Under certain situations, the front air conditioner may shed when running under generator power.  Both the cause and the solution are simple.

One of the big advantages of the D is that it has a standard Intelletic Energy Management System.  This allow the D to operate both a/c and other appliances when connected to 30 amps.  Without getting too technical, the EMS device senses the current being used and controls the operation of the a/c units. See Intelletic for details.  However, it also will not start the front a/c unless power is present, and it determines whether power is present from the current sensor.

When generator power is being used, there are two seperate power feeds.  One leg feeds power directly to the front a/c, and this leg does not pass through the EMS current sensor.  The other leg feeds the rear a/c and all other outlets.  Therefor, unless you have a significant load on the second power leg, the EMS will think that there is no power present and will not start the front a/c.

The solution is to put a load on the second power leg, such as the rear a/c or electric hot water heater.