Envoy 2WD V8-5.3L VIN M (2005)
Ambient Temperature Sensor / Switch HVAC: Service and Repair
AMBIENT AIR TEMPERATURE UPDATE PROCEDURE
The HVAC control module will not request compressor clutch engagement when the ambient air temperature display is less than 5 °C (40 °F). In order
to inspect compressor clutch operation during cold weather conditions, the vehicle must be brought inside and the ambient air temperature display must
be updated. To update the ambient air temperature display on the HVAC control module, perform the following procedure:
1. Turn ON the ignition.
2. Simultaneously press the MODE, FRONT DEFROST and REAR DEFROST switches.
