B104F

B104F-BLEND DOOR CONTROL CIRCUIT OPEN (SINGLE-ZONE)





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

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. 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 location of the open circuit and the direction the actuator is moving when the open is present.

- When Monitored:
During actuator calibration.

- Set Condition:
If Blend Door Actuator's electrical circuit is open. This DTC has a maturing time of 5 seconds and a de-maturing time of 10 seconds. If the DTCs status changes from active to stored it will stay in memory for 100 ignition cycles.





NOTE: This DTC must be active for the results of this test to be valid. Do not perform this test if this DTC is stored. Perform the HVAC System Test for stored DTC test procedures. HVAC System Test

1. CHECK FOR ACTIVE CONTROL CIRCUIT/PERFORMANCE DTCs
1. Turn the ignition on.
2. 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 BLEND DOOR ACTUATOR CIRCUIT RESISTANCE




1. Turn the ignition off.
2. Disconnect the A/C Heater Control C1 harness connector.
3. 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 above 70 Ohms?

Yes

- Go To 3

No

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

3. CHECK (C61) BLEND DOOR DRIVER CIRCUIT FOR AN OPEN




1. Disconnect the Blend Door Actuator harness connector.
2. Measure the resistance of the (C61) Blend Door Driver circuit between the A/C Heater Control C1 harness connector and the Blend Door Actuator harness connector.

Is the resistance below 5.0 Ohms?

Yes

- Go To 4

No

- Repair the (C61) Blend Door Driver circuit for an open.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

4. CHECK (C34) COMMON DOOR DRIVER CIRCUIT FOR AN OPEN




1. Measure the resistance of the (C34) Common Door Driver circuit between the A/C Heater Control C1 harness connector and the Blend Door Actuator harness connector.

Is the resistance below 5.0 Ohms?

Yes

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

No

- Repair the (C34) Common Door Driver circuit for an open.
- Perform the BODY VERIFICATION TEST. Body Verification Test.