Chrysler 300/300 Touring/300C, Dodge Magnum. Manual — part 2257

12.

VERIFY THAT THE FAULT IS STILL PRESENT

Reconnect the A/C Heater Control C2 harness connector.

Reconnect all of the door actuator harness connectors.

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, simulta-
neously press the A/C mode switch and the EBL mode switch down until both LEDs start flashing (approxi-
mately 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 44?

Yes

>> Replace the A/C Heater Control in accordance with the Service Information.

Perform BODY VERIFICATION TEST – VER 1. (Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL
MODULES/FRONT CONTROL MODULE - DIAGNOSIS AND TESTING).

No

>> Using the wiring diagram as a guide, inspect the wiring and connectors for conditions causing an inter-

mittent short that set the original fault. Repair as necessary. Then, if present, diagnose and repair all
other DTCs. Refer to the Table of Contents in this Section for a complete list of HVAC related symp-
toms.

Perform BODY VERIFICATION TEST – VER 1. (Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL
MODULES/FRONT CONTROL MODULE - DIAGNOSIS AND TESTING).

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45–BLEND DOOR BOUND (MTC)

For a complete wiring diagram Refer to Section 8W.

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Theory of Operation

NOTE: Diagnose and repair Actuator Circuit Test faults (DTC 61, 62, 63, 64, 67, 68, 69, 71, and 72) before
diagnosing Overcurrent faults (DTC 41, 43, and 44) and Calibration faults (DTC 18, 21, 22, 23, 45, 46, 47, 51,
52, 53, 55, and 56). Diagnose and repair Overcurrent faults (DTC 41, 43, and 44) before diagnosing Calibra-
tion faults (DTC 18, 21, 22, 23, 45, 46, 47, 51, 52, 53, 55, and 56).

The purpose of actuator calibration is to determine the total span of door travel between physical stops. To calibrate
the actuator, the A/C Heater Control first moves the door to its soft stop, and then counts the number of pulses it
takes to move the door to its other stop. An expected range of span is stored in the control’s memory. If the A/C
Heater Control detects no commutator pulses when calibrating the left blend door, this DTC will set.

•

When Monitored:
During actuator calibration.

•

Set Condition:
If the A/C Heater Control detects no commutator pulses when calibrating the left blend door.

Possible Causes

ACTUATOR CIRCUIT TEST FAULTS PRESENT

OVERCURRENT FAULTS PRESENT

(C255) LEFT BLEND DOOR DRIVER CIRCUIT OPEN

(C55) LEFT BLEND DOOR COMMON DRIVER CIRCUIT OPEN

LEFT BLEND DOOR SEIZED, OBSTRUCTED

LEFT BLEND DOOR ACTUATOR

A/C HEATER CONTROL

Diagnostic Test

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, simulta-
neously press the A/C mode switch and the EBL mode switch down until both LEDs start flashing (approxi-
mately 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,

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71, or 72?

Yes

>> 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
Table Of Contents in this section for a complete list of HVAC related symptoms.

No

>> Go To 2

2.

CHECK THE LEFT BLEND DOOR ACTUATOR CIRCUIT RESISTANCE

Turn the ignition off.

Disconnect the A/C Heater Control C2 harness connector.

Measure the resistance between the (C255) Left Blend Door Driver cir-
cuit 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

>> Go To 3

No

>> Go To 5

3.

CHECK THE (C255) LEFT BLEND DOOR DRIVER CIRCUIT FOR AN OPEN

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

>> Go To 4

No

>> Repair the (C255) Left Blend Door Driver circuit for an

open.

Perform BODY VERIFICATION TEST – VER 1. (Refer to 8
-

ELECTRICAL/ELECTRONIC

CONTROL

MODULES/

FRONT CONTROL MODULE - DIAGNOSIS AND TEST-
ING).

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