2007 Commander XK Factory Service Manual 24 - HEATING & AIR CONDITIONING

B10A6-LEFT BLEND DOOR TRAVEL RANGE TOO SMALL (ATC)

For a complete wiring diagram Refer to Section 8W.

Theory of Operation


The A/C Heater Control calibrates each actuator individually. Automatic calibration occurs upon power up after installing a new A/C Heater Control. Manual calibration occurs by sending a command with the scan tool. The purpose of actuator calibration is to determine the total span of door travel between physical stops. To calibrate the actuator, the A/C Heater Control first moves the door to its soft stop, and then counts the number of pulses it takes to move the door to its other stop. An expected range of span is stored in the control's memory. If the measured calibration value is less than the expected range for this actuator, this DTC will set. Note that the control clears all stored calibration faults at the beginning of the calibration procedure.



Possible Causes
 
DOOR DRIVER ELECTRICAL CIRCUIT(S)
 
LEFT BLEND DOOR SEIZED, BINDING, OBSTRUCTED
 
LEFT BLEND DOOR ACTUATOR
 
A/C HEATER CONTROL
 




Diagnostic Test

1. CHECK FOR ACTIVE CONTROL CIRCUIT/PERFORMANCE & CONTROL CIRCUIT OPEN DTCs

Turn the ignition on.
With the scan tool, read active HVAC DTCs.

Does the scan tool display any active: XXXX CONTROL CIRCUIT/PERFORMANCE or XXXX CONTROL CIRCUIT OPEN DTCs?

Yes


No

2. INSPECT ACTUATOR & HOUSING ASSEMBLY FOR A CONDITION CAUSING THE LEFT BLEND DOOR TO SEIZE OR BIND

Turn the ignition off.
Inspect the actuator, linkage, and housing assembly for a condition causing the left blend door to seize or bind.

Are there any physical or mechanical problems with the door, housing, linkage, or actuator?

Yes


No

3. CHECK LEFT BLEND DOOR TRAVEL

Remove the Left Blend Door Actuator from the A/C Heater Housing Assembly.
By hand, attempt to rotate the door in both directions. The door should operate smoothly in both directions over the entire span of travel (approximately 90 degrees).

Does the door operate smoothly in both directions over the entire span of travel?

Yes


No

4. RUN THE ACTUATOR CALIBRATION TEST

Turn the ignition on.
With the scan tool, select System Tests and then select Actuator Calibration Test. When the test is complete, select View DTCs.

Does the scan tool display: B10A6–LEFT BLEND DOOR TRAVEL RANGE TOO SMALL?

Yes


No