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) VERIFY IF ANY ACTUATOR CIRCUIT TEST FAULTS OR OVERCURRENT FAULTS ARE PRESENT
Turn the ignition on.

Actuate the Clear DTC function by performing the following:
- Turn the blower control on.
- Press the A/C mode switch down, turn the blower control to off, wait until both LEDs illuminate (approximately 5 seconds) and then release the A/C mode switch.
- When the A/C status indicator begins displaying DTCs, set the Mode switch to the floor position, simultaneously press the A/C mode switch and the EBL mode switch down until both LEDs start flashing (approximately 5 seconds) and then release the mode switches. Stored DTCs will clear from memory in approximately two seconds.
Turn the ignition off, wait 10 seconds, and turn the ignition on.

Actuate the Actuator Circuit Test / Door Calibration Function by performing the following:
- Turn the blower control off.
- Press and hold the EBL mode switch down and then turn the blower control on. Continue to hold the EBL mode switch down until the EBL status indicator begins flashing. Then, release the EBL mode switch. While the test / function is running, the EBL status indicator will flash once per second. If the test / function passes, the EBL status indicator will stop flashing. If the test / function fails, the A/C and EBL status indicators will flash alternately. Allow the test / function to run to completion before proceeding.
Actuate the Display DTC function by performing the following:
- Turn the blower control on.
- Press the A/C mode switch down, turn the blower control to off, wait until both LEDs illuminate (approximately 5 seconds) and then release the A/C mode switch.
NOTE: The A/C status indicator displays active DTCs when the EBL status indictor is not illuminated and stored DTCs when the EBL status indicator is illuminated.

Read DTCs from the A/C status indictor.

Does the A/C status indicator display any of the following DTCs: 41, 43, 44, 61, 62, 63, 64, 67, 68, 69, 71, or 72?

Yes
1. As present, diagnose and repair the faults in the following order: DTC 72 first, then DTC 62, then DTC 61, then DTCs 64, 68, or 71, then DTCs 63, 67, or 69, and finally DTCs 41, 43, or 44. Refer to the DIAGNOSTIC CODE INDEX for a complete list of HVAC related symptoms.
No
1. Go To step 2).
2) CHECK THE LEFT BLEND DOOR ACTUATOR CIRCUIT RESISTANCE

Fig 1: Measuring Resistance Between Left Blend Door Common Driver & Left Blend Door 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 step 3).
No
1. Go To step 5).
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 A/C Heater Control C2 harness connector and the Left Blend Door Actuator harness connector.

Is the resistance below 5.0 ohms?

Yes
1. Go To step 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: Checking 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 A/C Heater Control C2 harness connector and the Left Blend Door Actuator 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) .
5) INSPECT ACTUATOR & HOUSING ASSEMBLY FOR A CONDITION CAUSING THE LEFT BLEND DOOR TO SEIZE
Turn the ignition off.

Inspect the actuator, linkage, and housing assembly for a condition causing the left blend door to seize.

Are there any physical or mechanical problems with the door, housing, linkage, or actuator?

Yes
1. Repair as necessary 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. Go To step 6).
6) CHECK LEFT BLEND DOOR TRAVEL
Remove the Left Blend Door Actuator from the A/C Heater Housing Assembly.

By hand, attempt to rotate the door in both directions. The door should operate smoothly in both directions over the entire span of travel (approximately 190 degrees).

Does the door operate smoothly in both directions over the entire span of travel?

Yes
1. Replace the Left Blend Door Actuator in accordance with the Service Information. Then, Go To step 7).
No
1. Repair as necessary 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) .
7) VERIFY IF THE FAULT IS STILL PRESENT
Turn the ignition on.

Actuate the Clear DTC function by performing the following:
- Turn the blower control on.
- Press the A/C mode switch down, turn the blower control to off, wait until both LEDs illuminate (approximately 5 seconds) and then release the A/C mode switch.
- When the A/C status indicator begins displaying DTCs, set the Mode switch to the floor position, simultaneously press the A/C mode switch and the EBL mode switch down until both LEDs start flashing (approximately 5 seconds) and then release the mode switches. Stored DTCs will clear from memory in approximately two seconds.
Turn the ignition off, wait 10 seconds, and turn the ignition on.

Actuate the Actuator Circuit Test / Door Calibration Function by performing the following:
- Turn the blower control off.
- Press and hold the EBL mode switch down and then turn the blower control on. Continue to hold the EBL mode switch down until the EBL status indicator begins flashing. Then, release the EBL mode switch. While the test / function is running, the EBL status indicator will flash once per second. If the test / function passes, the EBL status indicator will stop flashing. If the test / function fails, the A/C and EBL status indicators will flash alternately. Allow the test / function to run to completion before proceeding.
Actuate the Display DTC function by performing the following:
- Turn the blower control on.
- Press the A/C mode switch down, turn the blower control to off, wait until both LEDs illuminate (approximately 5 seconds) and then release the A/C mode switch.
NOTE: The A/C status indicator displays active DTCs when the EBL status indictor is not illuminated and stored DTCs when the EBL status indicator is illuminated.

Read DTCs from the A/C status indictor.

Does the A/C status indicator display DTC 45?

Yes
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) .
No
1. Perform BODY VERIFICATION TEST - VER 1. (Refer to ELECTRICAL/ELECTRONIC CONTROL MODULES/FRONT CONTROL MODULE - DIAGNOSIS AND TESTING) .