B0441

DTC B0441

CIRCUIT DESCRIPTION
The following DTCs are for the left and right air temperature actuators:
- B0441 is for the left air temperature actuator
- B0446 is for the right air temperature actuator

The HVAC control module commands the air temperature actuators to move by controlling the voltage supplied on the control circuit. A signal voltage of 0 volts or a signal voltage of 5 volts rotates the air temperature actuator. A voltage of 2.5 volts stops the door. The HVAC control module determines the current position of the actuator by monitoring the feedback voltage of the air temperature door position signal circuit. The feedback potentiometer position is a function of the air temperature actuator. The HVAC control module controls the air temperature door position in order to maintain the selected air temperature.

Whenever the HVAC control module keep alive memory battery power is interrupted, the HVAC control module will perform a recalibration of the actuators.

During recalibration, the HVAC control module will drive the air temperature actuators to their minimum and maximum travel extremes. The HVAC control module will then calculate a travel range from this data and compare it to a calibrated range within the HVAC control module. If the actual travel range is not within the calibrated expected range, the actuator will be considered not calibrated and the DTC will set.

CONDITIONS FOR RUNNING THE DTC
- The ignition is turned ON.
- The HVAC control module power must be interrupted.

CONDITIONS FOR SETTING THE DTC
The air temperature actuator actual total travel range is less than or more than the calibrated limits.

ACTION TAKEN WHEN THE DTC SETS
- The HVAC control module will continue to make use of whatever air temperature actuator travel range is still available.
- Each time the ignition switch is turned ON the HVAC control module will perform a recalibration of the actuator.

CONDITIONS FOR CLEARING THE DTC
The air temperature actuator travel range error must be corrected.

DIAGNOSTIC AIDS
- The range fault code can only be detected following a check of the air temperature actuator travel range. The air temperature actuator travel range check can only be initiated by disrupting power to the HVAC control module or with the scan tool.
- The calibration limit is 147-220 counts (2.9-4.4 V). An actual range below this limit suggests an obstruction, something stuck in the door limiting travel.
An actual range above this limit suggests an over travel condition, damaged or missing foam seals.
- If condition not present, refer to Testing for Intermittent and Poor Connections in Diagnostic Aids.

TEST

Step 1:

Steps 2-5:

Step 6:

Steps 7-8:

Steps 9-13: