I just had another thought. When I jumpered the high pressure sensor connection, there was +12V going through the jumper. Wouldn't that indicate that the Heater Control Assembly is working properly as it is allowing power to get to both sensors.
Ah! That gives me another thought...I think at one point in my troubleshooting yesterday I was not getting power to the sensors, but looking back, I'm not sure I had the switch in the A/C position.
Would that make sense?
Sorry for the "thinking out loud". I'm not neccessarily a mechanic by any means as you can probably tell, and this has definitely been a great learning experience. I greatly appreciate all your help so far WMBurns!
Look at your diagram. If you have +12 volts going to the low pressure switch, then the AC dash control MUST be in the AC position. The diagram says it has to be so.
To say there is only 1 relevant fuse is silly. The diagram points out two. I can't begin to tell you the number of times I have helped PPL that it turned out to be a blown fuse. Either they "looked" at it from above, or "checked it" at the start of work. Only to find out later that it was blown. So do yourself a favor and check all of the fuses. Pull them out one at a time and look at them from the side. Even better, test them with an Ohm meter. It may turn out that your CCRM is bad. However, wouldn't you feel dumb if it still did not work after the repair?
Yes the CCRM is a PIA to get to. Best to remove the right hand fender liner to access.
Have you verified there is Freon in the system?
FWIIW, per the diagram, the high pressure switch is a normally closed (NC) contact. The best way to test a NC switch is to disconnect and test with an OHM meter (or noid light or what ever you have to test basic circuit continunity). The only sensor that needs to be jumpered is the low pressure swich and only if the AC is low on Freon.
Finally, do you have an ODB2 scanner? If so, monitor the AC PID to ensure that the PCM is even calling for AC.
IMO, assuming that you have done all of the other tests correctly and the fuse is in fact good, the odds do favor a bad CCRM.