B1040

B1040-PANEL MODE DOOR 1 CONTROL CIRCUIT/PERFORMANCE





For a complete wiring diagram Consult Diagrams/Electrical.

Theory of Operation

The A/C Heater Control drives the Mode Door Actuator via the (C35) Mode Door Driver circuit and the (C34) Common Door Driver circuit. The Mode Door Actuator does not share the (C34) Common Door Driver circuit or its driver inside the A/C Heater Control with any other actuator.

- When Monitored:
With the ignition on.

- Set Condition:
If the A/C Heater Control detects a short to ground or to voltage on the (C32) Recirculation Door Driver, the (C61) Blend Door Driver, or the (C34) Common Door Driver circuits while attempting to drive the (C35) Mode Door Driver.





Diagnostic Test

1. ACTIVE DTC(S) PRESENT
Turn the ignition on.
Using the A/C Heater Control, actuate the Mode Door.
With the scan tool, check for DTCs.
Does the scan tool display this DTC as active?

Yes

- Go to 2

No

- The condition that caused this symptom is currently not present. Check for an intermittent condition by inspecting the related wiring harness for chafed, pierced, pinched, and partially broken wires. Also, inspect the related connectors for broken, bent, pushed out, spread, corroded, or contaminated terminals. Repair as necessary.
- Perform the BODY VERIFICATION TEST - VER 1. Body Verification Test.

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




Turn the ignition off.
Disconnect the A/C Heater Control C1 harness connector.
Turn the ignition on.
Measure the voltage of the (C32) Recirculation Door Driver circuit in the A/C Heater Control C1 harness connector.
Is there any voltage present?

Yes

- Repair the (C32) Recirculation Door Driver circuit for a short to voltage.
- Perform BODY VERIFICATION TEST - VER 1.Body Verification Test.

No

- Go to 3.

3. CHECK (C35) MODE DOOR DRIVER CIRCUIT FOR A SHORT TO VOLTAGE




Measure the voltage of the (C35) Mode Door Driver circuit in the A/C Heater Control C1 harness connector.
Is there any voltage present?

Yes

- Repair the (C35) Mode Door Driver circuit for a short to voltage.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test.

No

- Go to 4.

4. CHECK (C61) BLEND DOOR DRIVER CIRCUIT FOR A SHORT TO VOLTAGE




Measure the voltage of the (C61) Blend Door Driver circuit in the A/C Heater Control C1 harness connector.
Is there any voltage present?

Yes

- Repair the (C61) Blend Door Driver circuit for a short to voltage.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test.

No

- Go to 5.

5. CHECK (C34) COMMON DOOR DRIVER CIRCUIT FOR A SHORT TO VOLTAGE




Measure the voltage of the (C34) Common Door Driver circuit in the A/C Heater Control C1 harness connector.
Is there any voltage present?

Yes

- Repair the (C34) Common Door Driver circuit for a short to voltage.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test.

No

- Go to 6.

6. CHECK (C32) RECIRCULATION DOOR DRIVER CIRCUIT FOR A SHORT TO GROUND




Turn the ignition off.
Measure the resistance between ground and the (C32) Recirculation Door Driver circuit in the A/C Heater Control C1 harness connector.
Does the ohm meter read open circuit?

Yes

- Go to 7.

No

- Repair the (C32) Recirculation Door Driver circuit for a short to ground.
- Perform BODY VERIFICATION TEST - VER 1.Body Verification Test.

7. CHECK (C61) DRIVER BLEND DOOR DRIVER CIRCUIT FOR A SHORT TO GROUND




Measure the resistance between ground and the (C61) Driver Blend Door Driver circuit in the A/C Heater Control C1 harness connector.
Does the ohm meter read open circuit?

Yes

- Go to 8.

No

- Repair the (C61) Driver Blend Door Driver circuit for a short to ground.
- Perform BODY VERIFICATION TEST - VER 1.Body Verification Test.

8. CHECK (C35) MODE DOOR DRIVER CIRCUIT FOR A SHORT TO GROUND




Measure the resistance between ground and the (C35) Mode Door Driver circuit in the A/C Heater Control C1 harness connector.
Does the ohm meter read open circuit?

Yes

- Go to 9.

No

- Repair the (C35) Mode Door Driver circuit for a short to ground.
- Perform BODY VERIFICATION TEST - VER 1.Body Verification Test.

9. CHECK (C34) COMMON DOOR DRIVER CIRCUIT FOR A SHORT TO GROUND




Measure the resistance between ground and the (C34) Common Door Driver circuit in the A/C Heater Control C1 harness connector.
Does the ohm meter read open circuit?

Yes

- Go to 10.

No

- Repair the (C34) Common Door Driver circuit for a short to ground.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test.

10. CHECK RECIRCULATION DOOR ACTUATOR CIRCUIT RESISTANCE




Measure the resistance between the (C32) Recirculation Door Driver circuit and the (C34) Common Door Driver circuit in the A/C Heater Control C1 harness connector.
Is the resistance between 30 and 40 ohms?

Yes

- Go to 11.

No

- Replace the Recirculation Door Actuator.
- Perform BODY VERIFICATION TEST - VER 1.Body Verification Test.

11. CHECK MODE DOOR ACTUATOR CIRCUIT RESISTANCE




Measure the resistance between the (C35) Mode Door Driver circuit and the (C34) Common Door Driver circuit in the A/C Heater Control C1 harness connector.
Is the resistance between 30 and 40 ohms?

Yes

- Go to 12.

No

- Replace the Mode Door Actuator.
- Perform BODY VERIFICATION TEST - VER 1.Body Verification Test.

12. CHECK BLEND DOOR ACTUATOR CIRCUIT RESISTANCE




Measure the resistance between the (C61) Blend Door Driver circuit and the (C34) Common Door Driver circuit in the A/C Heater Control C1 harness connector.
Is the resistance between 30 and 40 ohms?

Yes

- Go to 13.

No

- Replace the Blend Door Actuator.
- Perform BODY VERIFICATION TEST - VER 1.Body Verification Test.

13. RUN THE ACTUATOR CALIBRATION TEST
Reconnect the A/C Heater Control C1 harness connector.
Turn the ignition on.
With the scan tool, erase HVAC DTCs.
Turn the ignition off, wait 10 seconds, and then 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 only display: B1040-PANEL MODE DOOR 1 CONTROL CIRCUIT/PERFORMANCE?

Yes

- Replace the A/C Heater Control.
- Perform BODY VERIFICATION TEST - VER 1.Body Verification Test.

No, Other DTC(s) Displayed

- Diagnose and repair the DTC(s).

No, And No Other DTCs Displayed

- Using the wiring diagram as a guide, inspect the wiring and connectors for conditions causing an intermittent short. Repair as necessary.
- Perform BODY VERIFICATION TEST - VER 1.Body Verification Test.