2008 Contessa Dash Air Conditioning InOp

[Steve Huber Co-Admin]

Peter,
Looking at pg 116, 12v comes from F29 thru the vent control switch. It then runs to the fan and to the "amplifier" The fan switch selects the appropriate resistance to ground to control fan speed.
Steve

[Eric Maclean]

Peter
You have what is referred To as a pull down circuit . When you load the circuit there is a resistance somewhere in your 12 volt feed that can not support much or any current draw or load hence when you plug the controller back in the voltage is pulled down to zero.

First places to check are back at the fuse with the controller plugged in and blower turned on do you have 12 volts there
If yes move down the line untill you find the problem ( suspect any connectors, look for green connections or green fat wires that can be stretched.)

You may want to bypass the feed wording to test the rest of the system by connecting a known good power feed to the controller 12 volt power supply at the controller.

Hope this helps
Eric

[Peter Whiting]

I want to thank all those who offered advice.  The problem is solved.  By running 12vdc directly to the terminal A on the vent control plug, the blower and everything else worked.  This meant that the problem was in the supply voltage, not downstream like you would think.  Tracing back, the VCN connector on the Vehicle Cabin PCB, though appearing to be full seated (even wiggling it did not fix the issue), it was not.  Pulling the connector off and putting it back on and "Voila".......problem solved.

[Eric Maclean]

Peter
Glad to hear you got it solved .

I read a tee shirt the other day that read ( THE ONLY THING THAT WORKS ON THIS MOTORHOME IS THE OWNER) LOL
 No truer words where ever spoken.

Good luck
And happy trails
Eric

[Fred Brooks]

  Peter,
Often times when wiring male and female pins are installed into a connector, the "wings" on the pins do not travel far enough to lock into position. Consequently when both halves of the connector are pushed together, 1 pin can push the mating pin back out of the connector. Now even though the pins may be touching each other and giving you continuity, under a demand of amperage, it causes them to separate and give you an open circuit. When trouble shooting always inspect the pins on both sides for equal depth.
  Thanks Eric, It is an endless adventure that tests the depth of your resolve!
  Fred