| Subject: | HVAC Control Head Inoperative |
| Models: | 2007 Cadillac Escalade |
The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.
Condition/Concern:
Some customers may have a concern where the front HVAC control head is inoperative. The concern is intermittent and seems to happen more in cold weather. You may also notice there is no communication with the HVAC module when using the Tech 2. You also
may notice the concern stops when the C4 connector is cycled to the HVAC module.
Recommendation/Instructions:
If you experience this concern and the vehicle is corrected by cycling the connectors to the HVAC control head. Please do not replace the HVAC control head. A software calibration update is now available. Please update the HVAC software calibration using
TIS2000 version 3.5 or later that was released on 03/20/06. You may also access the latest software calibrations by using the TIS-2-Web application.
Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.
