Freightliner Bunk Heater Problem

[delta5]

Im driving a 2003 Century Class and I have a problem with my bunk heat/ac. The blower motor for the back unit will only work on the high speed setting. The front ac/heat works on all speed settings. Anyone have any idea what might be bad in the back?

[msimon]

look for a resistor in the duct work near the fan blower in the sleeper a/c unit. on my pete it has 3 pins that come out of the ducting with a 3 wire harness that plugs into the resistor. i just replaced that part on my truck and corrected the issue. a freightliner can't be that much different...good luck