2006 Jeep Commander
We have a 2006 Jeep Commander with manual temp control, Customer purchased a month ago. This had several issues, EVAP, No AC, No blower operation, several codes stored for HVAC(we replaced the control head), has a new NVLD assembly. When attempting to run EVAP test fuel gauge on dash and actual fuel level in tank did not match, now there are no leaks in EVAP system, let customer drive for a week. Now everything is functioning except AC operation and will not pass EVAP test, This appears to have a junk yard PCM part #P…AD installed, VIN matches, shows 4 door sedan, mileage does not match, AC is not allowed due to an incorrect input according to scan tool(control compensation input-Disabled) Has a new AC transducer, EVAP temp sensor appears to be reading 72 degrees. Still no AC operation, can operate AC through scan tool. With new control head, codes are not present. Not sure what we are missing.
On pin 4, connector c1 is the ac switch sense coming from the HVAC head unit. Well that pin 4 is CANbus - going to the cluster. I'd check that CAN signal and there's also a sun-sensor going to the HVAC head, you may want to check that as well. Even if there's no codes. Just a thought.
This is manual temp control so no sun load sensor, The instrument panel does see the signal from the AC control head when you turn on/off.
From service info, “For the MTC system, the A/C-heater control sends the request for A/C to the CCN via a dedicated mux circuit. The CCN then broadcasts the A/C request on the CAN B bus, where it is read and processed by the FCM, which in turn broadcasts it on the CAN C bus, where it is read and processed by the PCM." Access CCN (cluster) and FCM (front control module) to check for A/C request…
You might try a different scan tool. Since yours will show you "disabled" but nothing else in any data list looks outta-whack, then I suggest some data is missing from a list. 2006 CryCorp CAN vehicles were StarScan cars, and then Star Mobile.....(pre- wiTech days).