B1909-12

B1909-12-RECIRCULATION DOOR CONTROL - CIRCUIT SHORT TO BATTERY





For a complete wiring diagram, refer to the Wiring Information.

Theory of Operation

After the initial installation of the A/C Heater Control, the controller is calibrated to each individual door actuator. The recirculation door actuator is connected to the A/C heater control or module by a dedicated two-wire lead and connector of the HVAC wire harness.When the A/C Heater Control pulls the voltage on one side of the control circuit high and the other low, the door actuator will move in one direction. When the A/C Heater Control reverses the polarity of the voltage to the motor, the recirculation door actuator moves in the opposite direction. When the recirculation air door reaches its travel limit, the A/C heater control will turn the voltage off. Unlike the mode and blend door actuators, the recirculation door does not use a position sensor due to the door only has two positions of either open or closed. The A/C Heater Control learns the recirculation door stop positions during the calibration procedure.

- When Monitored:
Continuously with the ignition on.

- Set Condition:
The A/C Heater Control detects a short voltage on the Recirculation Door control circuit. If the A/C Heater Control detects a valid voltage, the DTC will change from Active to Stored and will stay in the controllers memory for 100 ignition cycles.





Always perform the HVAC Pre-Diagnostic Troubleshooting procedure before proceeding. Initial Inspection and Diagnostic Overview.

1. CHECK IF DTC IS ACTIVE
1. Ignition on, engine running.
2. Using the HVAC controls, switch recirculation mode on and off several times.
3. With the scan tool, read HVAC DTCs.

Is this DTC active?

Yes

- Go To 2

No

- Go To 5

2. CHECK THE (C32) RECIRCULATION DOOR DRIVER CIRCUIT FOR A SHORT TO VOLTAGE




1. Turn the ignition off to the lock position.
2. Disconnect the A/C Heater Control C1 harness connector.
3. Disconnect the Recirculation Door Actuator harness connector.
4. Ignition on, engine not running.
5. Measure the voltage of the (C32) Recirculation Door Driver circuit.

Is there any voltage present?

Yes

- Repair the (C32) Recirculation Door Driver circuit for a short to voltage.
- Perform the HVAC VERIFICATION TEST. HVAC Verification Test.

No

- Go To 3

3. CHECK THE (C68) RECIRCULATION DOOR COMMON DRIVER CIRCUIT FOR A SHORT TO VOLTAGE




1. Measure the voltage of the (C68) Recirculation Door Common Driver circuit.

Is there any voltage present?

Yes

- Repair the (C68) Recirculation Door Common Driver circuit for a short to voltage.
- Perform the HVAC VERIFICATION TEST. HVAC Verification Test.

No

- Go To 4

4. CHECK THE RECIRCULATION DOOR ACTUATOR
1. Turn the ignition off to the lock position.
2. Replace the Recirculation Door Actuator. Recirculation Door Actuator - Removal.
3. Reconnect all previously disconnected connectors.
4. Ignition on, engine not running.
5. Using the scan tool, erase HVAC DTCs.
6. Using the scan tool, perform the HVAC Actuator Calibration Test.
7. Turn the ignition off to the lock position for 30 seconds.
8. Ignition on, engine running.
9. Using the HVAC controls, switch recirculation mode on and off several times.
10. With the scan tool, read HVAC DTCs.

Did this DTC reset?

Yes

- Replace and program the A/C Heater Control. A/C And Heater Control - Removal.
- Perform the HVAC VERIFICATION TEST. HVAC Verification Test.

No

- Test complete.
- Perform the HVAC VERIFICATION TEST. HVAC Verification Test.

5. CHECK THE WIRING AND CONNECTORS
1. The conditions necessary to set the DTC are not present at this time.
2. With the scan tool, check the Environmental Data to help identify the conditions in which the DTC was set.
3. Using the wiring diagrams as a guide, check all related splices and connectors for signs of water intrusion, corrosion, pushed out or bent terminals, and correct pin tension.
4. Wiggle the wiring and connectors while checking for shorted and open circuits.

Were there any problems found?

Yes

- Repair as necessary.
- Perform the HVAC VERIFICATION TEST. HVAC Verification Test.

No

- Test complete.