Climate Control Motor(s) Common 1 Control Circuit Low (Single-Zone)

B105F-CLIMATE CONTROL MOTOR(S) COMMON 1 CONTROL CIRCUIT LOW (SINGLE-ZONE)

B105F-Climate Control Motor(s) Common 1 Control Circuit Low (Single-Zone):

Theory of Operation
The A/C Heater Control drives the Blend Door Actuator via the (C61) Blend Door Driver circuit and the (C34) Common Door Driver circuit. The A/C Heater Control drives the Mode Door 1 (Panel to Floor) Actuator via the (C29) Mode Door 1 Driver circuit and the (C34) Common Door Driver circuit. The A/C Heater Control drives the Mode Door 2 (Defrost to Floor) Actuator via the (C801) Mode Door 2 Driver circuit and the (C34) Common Door Driver circuit. The A/C Heater Control drives the Recirculation Door Actuator via the (C32) Recirculation Door Driver circuit and the (C34) Common Door Driver circuit. All of the door actuators share the (C34) Common Door Driver circuit. Inside the A/C Heater Control, each door actuator has its own unique driver, but all share a single common door driver circuit. Due to the shared circuitry similar DTCs can set at the same time for multiple actuators depending upon the type of short, its location, and the direction the actuator is moving when the short is present.

WHEN MONITORED
When the Actuator DTC Detection Test is executed.

SET CONDITION
If the (C34) Common Door Driver circuit is shorted to ground.

POSSIBLE CAUSES
- (C34) common door driver circuit shorted to ground
- (C34) common door driver circuit shorted to other door driver circuit(s)
- Blend door actuator
- Mode door 1 (panel to floor) actuator
- Mode door 2 (defrost to floor) actuator
- Recirculation door actuator
- A/C heater control

DIAGNOSTIC TEST

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




Turn the ignition off.
Disconnect the A/C Heater Control C1 harness connector.
Measure the resistance of the (C34) Common Door Driver circuit between ground and the A/C Heater Control C1 harness connector.

Q: Is the resistance below 10k ohms?

YES: Repair the (C34) Common Door Driver circuit for a short to ground.
Perform BODY VERIFICATION TEST - VER 1. Body Verification Test
NO: Go To 2

2. 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.

Q: Is the resistance below 30 ohms?

YES: Go To 3
NO: Go To 4

3. CHECK (C61) BLEND DOOR DRIVER CIRCUIT FOR A SHORT TO (C34) COMMON DOOR DRIVER CIRCUIT




Disconnect the Blend Door Actuator harness connector.
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.

Q: Is the resistance below 10k ohms?

YES: Repair the (C61) Blend Door Driver Circuit for a short to the (C34) Common Door Driver circuit.
Perform BODY VERIFICATION TEST - VER 1. Body Verification Test
NO: Replace the Blend Door Actuator.
Perform BODY VERIFICATION TEST - VER 1. Body Verification Test

4. CHECK MODE DOOR 2 (DEFROST TO FLOOR) ACTUATOR CIRCUIT RESISTANCE




Measure the resistance between the (C801) Mode Door 2 Driver circuit and the (C34) Common Door Driver circuit in the A/C Heater Control C1 harness connector.

Q: Is the resistance below 30 ohms?

YES: Go To 5
NO: Go To 6

5. CHECK (C801) MODE DOOR 2 DRIVER CIRCUIT FOR A SHORT TO (C34) COMMON DOOR DRIVER CIRCUIT




Disconnect the Mode Door 2 (Defrost to Floor) Actuator harness connector.
Measure the resistance between the (C801) Mode Door 2 Driver circuit and the (C34) Common Door Driver circuit in the A/C Heater Control C1 harness connector.

Q: Is the resistance below 10k ohms?

YES: Repair the (C801) Mode Door 2 Driver Circuit for a short to the (C34) Common Door Driver circuit.
Perform BODY VERIFICATION TEST - VER 1. Body Verification Test
NO: Replace the Mode Door 2 (Defrost to Floor) Actuator.
Perform BODY VERIFICATION TEST - VER 1. Body Verification Test

6. CHECK MODE DOOR 1 (PANEL TO FLOOR) ACTUATOR CIRCUIT RESISTANCE




Measure the resistance between the (C29) Mode Door 1 Driver circuit and the (C34) Common Door Driver circuit in the A/C Heater Control C1 harness connector.

Q: Is the resistance below 30 ohms?

YES: Go To 7
NO: Go To 8

7. CHECK (C29) MODE DOOR 1 DRIVER CIRCUIT FOR A SHORT TO (C34) COMMON DOOR DRIVER CIRCUIT




Disconnect the Mode Door 1 (Panel to Floor) Actuator harness connector.
Measure the resistance between the (C29) Mode Door 1 Driver circuit and the (C34) Common Door Driver circuit in the A/C Heater Control C1 harness connector.

Q: Is the resistance below 10k ohms?

YES: Repair the (C29) Mode Door 1 Driver Circuit for a short to the (C34) Common Door Driver circuit.
Perform BODY VERIFICATION TEST - VER 1. Body Verification Test
NO: Replace the Mode Door 1 (Panel to Floor) Actuator.
Perform BODY VERIFICATION TEST - VER 1. Body Verification Test

8. 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.

Q: Is the resistance below 30 ohms?

YES: Go To 9
NO: Go To 10

9. CHECK (C32) RECIRCULATION DOOR DRIVER CIRCUIT FOR A SHORT TO (C34) COMMON DOOR DRIVER CIRCUIT




Disconnect the Recirculation Door Actuator harness connector.
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.

Q: Is the resistance below 10k ohms?

YES: Repair the (C32) Recirculation Door Driver circuit for a short to the (C34) Common Door Driver circuit.
Perform BODY VERIFICATION TEST - VER 1. Body Verification Test
NO: Replace the Recirculation Door Actuator.
Perform BODY VERIFICATION TEST - VER 1. Body Verification Test

10. RUN THE ACTUATOR DTC DETECTION TEST
Reconnect the A/C Heater Control C1 harness connector.
Turn the ignition on.
With the scan tool in HVAC, select System Tests and then select Actuator DTC Detection. When the test is complete, select View DTCs.

Q: Does the scan tool only display: B105F-CLIMATE CONTROL MOTOR(S) COMMON 1 CONTROL CIRCUIT LOW?

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 other DTC(s). If multiple DTCs are present, beginning with the common circuit, diagnose and repair all short high DTCs and then all short low DTCs. Refer to Trouble Code Diagnostic Charts for a complete list of HVAC related symptoms.

No, And No 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