B0419

DTC B0419

CIRCUIT DESCRIPTION
- B0126 is for the mode actuator.
- B0409 is for the driver air temperature actuator.
- B0419 is for the passenger air temperature actuator.

The HVAC door actuator is an electronic motor with a feedback potentiometer. The HVAC control module supplies power and ground to the actuator. The HVAC control module controls the direction of the actuator by changing the polarity of the control circuit. When the actuator reaches the desired position, voltage is removed from the control circuit. The HVAC control module determines the current position of the actuator by monitoring the feedback voltage of the door position signal circuit. The feedback potentiometer position is a function of the actuator position.

CONDITIONS FOR RUNNING THE DTC
- The ignition is ON.
- Ignition voltage is between 9-16 volts.

CONDITIONS FOR SETTING THE DTC
The actual door position differs from the commanded door position by 4 counts or greater for more than 16 seconds.

ACTION TAKEN WHEN THE DTC SETS
The HVAC control module will not command actuator movement past the point where the stall condition is detected and will continue to make use of the remaining nonrestricted range.

CONDITIONS FOR CLEARING THE DTC
- The DTC will become history if the HVAC control module no longer detects the condition that set the DTC.
- The history DTC will clear after 50 fault free ignition cycles.
- The DTC can be cleared with a scan tool.

DIAGNOSTIC AIDS
- The condition may be intermittent.
- Inspect the appropriate HVAC door and actuator for the following conditions:
- A misaligned door actuator
- Broken or binding linkages or door
- An obstruction that prevents the door from operating within its full range of motion

TEST DESCRIPTION

Steps 1-2:

Steps 3-6:

Steps 7-11:

Steps 12-15:

Steps 16-18:

The number below refers to the step number on the diagnostic table.
5. This step verifies that the HVAC control module is able to command the appropriate HVAC actuator through its full range of motion.