OK OK I was just waiting to see if anybody was really paying attention to this post. Here's the deal, after spending a whole day testing out and checking things this is what I found. The AC chassis thermostat was bad. I could not figure out why as there was no power going back to the AC compressor or the high-pressure switch so I started looking around for other relays or switches that may be bad. All checked out OK, went to the thermostat that's mounted on the black box on the front of the coach is where the heater core and evaporator is located in the upper left-hand corner. I had power on one side but no power on the other side. There are two wires on the thermostat, one's blue and one's yellow. The blue wire has power but no power to the yellow. There should be power going to both wires all the time when the ignition switch is turned on. Pull those two wires off and use a jumper wire for this test. With the coach off turn the ignition key on with the AC on normal, go out to the front of your coach. Pull those two wires off and check the blue wire with a test light for power. There should be power on the blue wire. Now jump that to the yellow wire. If the chassis condenser electric fan kicks on, you know you have a bad thermostat. To confirm the thermostat is really bad, put the two wires back on the thermostat and use a test light to the yellow wire. No power means the thermostat is bad. Here's a picture of the thermostat. Make sure when you remove the thermostat, pull it straight out and you will see the coil and where it is pushed into the evaporator. You have to measure the distance on the coil from the old one to the new one.
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