B105C
B105C-RECIRCULATION DOOR TRAVEL RANGE TOO SMALL
For a complete wiring diagram refer to Diagrams/Electrical.
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 an end 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.
- When Monitored:
During actuator calibration.
- Set Condition:
If the total span of the Recirculation Door is less than the low range limit.
Diagnostic Test
1. CHECK FOR ACTIVE CONTROL CIRCUIT/PERFORMANCE DTCs
Turn the ignition on.
With the scan tool, read active HVAC DTCs.
Does the scan tool display any active: XXXX CONTROL CIRCUIT/PERFORMANCE DTCs?
Yes
- Diagnose and repair the DTC(s).
No
- Go To 2
2. CHECK FOR ACTIVE CONTROL CIRCUIT OPEN DTCs
With the scan tool, read active HVAC DTCs.
Does the scan tool display any active: XXXX CONTROL CIRCUIT OPEN DTCs?
Yes
- Diagnose and repair the DTC(s).
No
- Go To 3
3. RUN THE ACTUATOR DTC DETECTION TEST
With the scan tool in HVAC, select System Tests and then select Actuator DTC Detection. When the test is complete, select View DTCs.
Does the scan tool display any DTCs?
Yes, Dual-Zone System
- Diagnose and repair the DTC(s). If multiple DTCs are present, beginning with the passenger blend door, diagnose and repair all short high DTCs and then all short low DTCs.
Yes, Single-Zone System
- Diagnose and repair the DTC(s). If multiple DTCs are present, beginning with the common circuit, diagnose and repair all short high DTCs first and then all short low DTCs.
No
- Go To 4
4. INSPECT ACTUATOR & HOUSING ASSEMBLY FOR A CONDITION CAUSING THE DOOR TO SEIZE OR BIND
Turn the ignition off.
Inspect the actuator and the housing assembly for a condition causing the door to seize or bind.
Are there any physical or mechanical problems with the door, housing, or actuator?
Yes
- Repair as necessary.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test
No
- Go To 5
5. CHECK RECIRCULATION DOOR TRAVEL
Remove the Recirculation 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 approximately 95 degrees of travel.
Does the door operate smoothly in both directions over approximately 95 degrees of travel?
Yes
- Replace the Recirculation Door Actuator. Then, Go To 6
No
- Repair as necessary.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test
6. RUN 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: B105C-RECIRCULATION DOOR TRAVEL RANGE TOO SMALL?
Yes
- Replace the A/C Heater Control.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test
No
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test