Chrysler 300/300 Touring/300C, Dodge Magnum. Manual — part 2287

3.

CHECK MODE, BLEND & RECIRCULATION DOOR OPERATION

Start the engine.

Set the blower to high speed.

Verify that air flows from the correct vents while setting the Mode control to the Panel position, the Bilvel position,
the Floor/Defrost position, and the Defrost position. Then, repeat in the opposite direction.

Set the Mode control to the Panel position.

Set the Driver Blend control to the full cold position.

Set the Passenger Blend control the full cold position.

Verify that the airflow air temperature changes while setting the Driver Blend control to the full hot position. Then,
repeat in the opposite direction.

Verify that the airflow air temperature changes while setting the Passenger Blend control to the full hot position.
Then, repeat in the opposite direction.

Set the Mode control to any position between Floor and Panel.

Press the Recirc function on. Verify that the sound of the airflow gets louder as the recirculation door opens to bring
in recirculated air.

Press the Recirc function off. Verify that the sound of the airflow gets softer as the recirculation door closes to bring
in fresh air.

Does each door operate properly?

Yes

>> The condition causing the fault has cleared at this time.

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

No

>> Remove the door actuator of the affected door from the A/C Heater Housing Assembly. By hand,

attempt to rotate the actuator in both directions. Inspect the A/C Heater Housing for damage, for dis-
connected, missing, or broken linkage, and for broken or binding doors. Repair as necessary in accor-
dance with the Service Information.

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

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B10A9–RIGHT BLEND DOOR CONTROL CIRCUIT/PERFORMANCE (ATC)

For a complete wiring diagram Refer to Section 8W.

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Theory of Operation

The A/C Heater Control monitors the door driver circuits during actuator operation for shorts to ground, shorts to
battery, and shorts to other door driver circuits. If detected, the A/C Heater Control reports these types of faults as
Control Circuit/Performance DTCs.

•

When Monitored:
When actuator movement is requested.

•

Set Condition:
If the A/C Heater Control detects an excessive current draw on any of the door driver circuits while attempting
to drive this door actuator.

Possible Causes

DOOR DRIVER CIRCUIT(S) SHORTED TO VOLTAGE

DOOR DRIVER CIRCUIT(S) SHORTED TO GROUND

DOOR DRIVER CIRCUITS SHORTED TOGETHER

DOOR ACTUATOR(S)

A/C HEATER CONTROL

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. Refer to HVAC System Test (ATC) for stored DTC test procedures.

Diagnostic Test

1.

CHECK THE DOOR DRIVER CIRCUITS FOR A SHORT TO VOLTAGE

Turn the ignition off.

Disconnect the A/C Heater Control C2 harness connector.

Turn the ignition on.

Measure the voltage of the (C266) Mode Door Driver circuit, the (C66)
Mode Door Common Driver circuit, the (C255) Left Blend Door Driver
circuit, the (C55) Left Blend Door Common Driver circuit, the (C252)
Right Blend Door Driver circuit, the (C52) Right Blend Door Common
Driver circuit, the (C268) Recirculation Door Driver circuit, and the (C68)
Recirculation Door Common Driver circuit.

Is the voltage above 0.2 volts on any of the circuits?

Yes

>> Repair all circuits with voltage above 0.2 volts for a short to

voltage.

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

ELECTRICAL/ELECTRONIC

CONTROL

MODULES/

FRONT CONTROL MODULE - DIAGNOSIS AND TEST-
ING).

No

>> Go To 2

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2.

CHECK THE DOOR DRIVER CIRCUITS FOR A SHORT TO GROUND

Turn the ignition off.

Measure the resistance of the (C266) Mode Door Driver circuit, the
(C66) Mode Door Common Driver circuit, the (C255) Left Blend Door
Driver circuit, the (C55) Left Blend Door Common Driver circuit, the
(C252) Right Blend Door Driver circuit, the (C52) Right Blend Door
Common Driver circuit, the (C268) Recirculation Door Driver circuit, and
the (C68) Recirculation Door Common Driver circuit between ground
and the A/C Heater Control C2 harness connector.

Is the resistance below 10k ohms on any of the circuits?

Yes

>> Repair all circuits with a resistance below 10k ohms for a

short to ground.

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

ELECTRICAL/ELECTRONIC

CONTROL

MODULES/

FRONT CONTROL MODULE - DIAGNOSIS AND TEST-
ING).

No

>> Go To 3

3.

CHECK THE (C266) MODE DOOR DRIVER CIRCUIT FOR A SHORT TO THE (C255) LEFT BLEND DOOR
DRIVER CIRCUIT, THE (C55) LEFT BLEND DOOR COMMON DRIVER CIRCUIT, THE (C252) RIGHT BLEND
DOOR DRIVER CIRCUIT, THE (C52) RIGHT BLEND DOOR COMMON DRIVER CIRCUIT, THE (C268)
RECIRCULATION DOOR DRIVER CIRCUIT, & THE (C68) RECIRCULATION DOOR COMMON DRIVER
CIRCUIT

Measure the resistance between the (C266) Mode Door Driver circuit
and the (C255) Left Blend Door Driver circuit, the (C55) Left Blend
Door Common Driver circuit, the (C252) Right Blend Door Driver circuit,
the (C52) Right Blend Door Common Driver circuit, the (C268) Recir-
culation Door Driver circuit, and the (C68) Recirculation Door Common
Driver circuit.

Is the resistance below 10k ohms on any of the circuits?

Yes

>> Repair all circuits with a resistance below 10k ohms for a

short to the (C266) Mode Door Driver circuit.

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

ELECTRICAL/ELECTRONIC

CONTROL

MODULES/

FRONT CONTROL MODULE - DIAGNOSIS AND TEST-
ING).

No

>> Go To 4

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