B0233

CIRCUIT DESCRIPTION
The air temperature actuator is an electronic stepper motor without a feedback circuit. It responds to voltage inputs from the HVAC control module with precalibrated non-adjustable position settings. The HVAC control module adjusts the air temperature actuator position to maintain the air temperature selected by the vehicle occupants.

CONDITIONS FOR RUNNING THE DTC
^ The ignition is turned ON.
^ DTC B1327 must not be current.

CONDITIONS FOR SETTING THE DTC
The air temperature door control circuit is shorted to ground or shorted to B+ for more than 2 seconds.

ACTION TAKEN WHEN THE DTC SETS
Control of the air temperature door position will be disabled.

CONDITIONS FOR CLEARING THE DTC
^ The DTC will become history if the HVAC control module no longer detects a failure.
^ The history DTC will clear after 50 fault free ignition cycles.
^ The HVAC control module receives the clear code command from the scan tool.

TEST DESCRIPTION

Steps 1-9:

The numbers below refer to the step numbers on the diagnostic table.
2. The air temperature actuator can be driven to one of two positions using the COLD and HOT command keys on the scan tool. The scan tool displays module output as a percentage of maximum control voltage. It does not indicate true actuator or door position.
3. This step verifies that the air temperature actuator is receiving the control voltage.