Diagnostic Test

WARNING: This page is about a different car, the 2006 Dodge Magnum, 2006 Dodge Charger, and 2006 Chrysler 300. However, it is still accessible from the selected car via links, so may be relevant.

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
1. Diagnose and repair the DTC(s). Refer to the DIAGNOSTIC CODE INDEX for a complete list of all HVAC related symptoms.
No
1. Go To 2).
2) CHECK THE LEFT BLEND DOOR ACTUATOR CIRCUIT RESISTANCE

Fig 1: Measuring Resistance Between Left Blend Door Driver & Left Blend Door Common Driver Circuits
Courtesy of DAIMLERCHRYSLER CORP.

Turn the ignition off.

Disconnect the A/C Heater Control C2 harness connector.

Measure the resistance between the (C255) Left Blend Door Driver circuit and the (C55) Left Blend Door Common Driver circuit in the A/C Heater Control C2 harness connector.

Is the resistance above 70.0 ohms?

Yes
1. Go To 3).
No
1. Replace the A/C Heater Control in accordance with the Service Information.
2. Perform BODY VERIFICATION TEST - VER 1. (Refer to ELECTRICAL/ELECTRONIC CONTROL MODULES/FRONT CONTROL MODULE - DIAGNOSIS AND TESTING) .
3) CHECK THE (C255) LEFT BLEND DOOR DRIVER CIRCUIT FOR AN OPEN

Fig 2: Checking Left Blend Door Driver (B) Circuit For Open
Courtesy of DAIMLERCHRYSLER CORP.

Disconnect the Left Blend Door Actuator harness connector.

Measure the resistance of the (C255) Left Blend Door Driver circuit between the Left Blend Door Actuator harness connector and the A/C Heater Control C2 harness connector.

Is the resistance below 5.0 ohms?

Yes
1. Go To 4).
No
1. Repair the (C255) Left Blend Door Driver circuit for an open.
2. Perform BODY VERIFICATION TEST - VER 1. (Refer to ELECTRICAL/ELECTRONIC CONTROL MODULES/FRONT CONTROL MODULE - DIAGNOSIS AND TESTING) .
4) CHECK THE (C55) LEFT BLEND DOOR COMMON DRIVER CIRCUIT FOR AN OPEN

Fig 3: Check Left Blend Door Driver (A) Circuit For Open
Courtesy of DAIMLERCHRYSLER CORP.

Measure the resistance of the (C55) Left Blend Door Common Driver circuit between the Left Blend Door Actuator harness connector and the A/C Heater Control C2 harness connector.

Is the resistance below 5.0 ohms?

Yes
1. Replace the Left Blend Door Actuator in accordance with the Service Information.
2. Perform BODY VERIFICATION TEST - VER 1. (Refer to ELECTRICAL/ELECTRONIC CONTROL MODULES/FRONT CONTROL MODULE - DIAGNOSIS AND TESTING) .
No
1. Repair the (C55) Left Blend Door Common Driver circuit for an open.
2. Perform BODY VERIFICATION TEST - VER 1. (Refer to ELECTRICAL/ELECTRONIC CONTROL MODULES/FRONT CONTROL MODULE - DIAGNOSIS AND TESTING) .