Chrysler Voyager. Manual — part 287

Symptom:

*HVAC SYSTEM TEST - MTC

POSSIBLE CAUSES

ATTEMPT TO COMMUNICATE WITH THE PCM/ECM, THE BCM, AND THE FCM

CHECK FOR HVAC RELATED DTCS IN THE PCM/ECM

CHECK FOR BCM DTCS

CHECK FOR FCM DTCS

CHECK FOR ACTIVE HVAC DTCS AND SYSTEM TESTS FAULT MESSAGES

CHECK FOR HVAC RELATED DTCS IN THE PCM/ECM

MANUAL A/C SYSTEM TEST

TEST

ACTION

APPLICABILITY

1

Turn the ignition on.
With the DRBIII

t, attempt to communicate with the Powertrain/Engine Control

Module.
With the DRBIII

t, attempt to communicate with the Body Control Module.

With the DRBIII

t, attempt to communicate with the Front Control Module.

Was the DRBIII

t able to communicate with the PCM/ECM, the BCM, and the FCM?

All

Yes

→ Go To 2

No

→ Refer to the communication category for the related symptom(s).

Perform BODY VERIFICATION TEST - VER 1.

2

With the DRBIII

t, read Powertrain/Engine Computer DTCs.

Are any HVAC related DTCs present?

All

Yes

→ Refer to the Powertrain Diagnostic Procedures Manual for the

related symptom(s).
Perform BODY VERIFICATION TEST - VER 1.

No

→ Go To 3

3

With the DRBIII

t, read Body Computer DTCs.

Are any DTCs present?

All

Yes

→ Refer to the appropriate catagory for the related symptom(s).

Perform BODY VERIFICATION TEST - VER 1.

No

→ Go To 4

4

With the DRBIII

t, read Front Control Module DTCs.

Are any DTCs present?

All

Yes

→ For FCM DTCs related to the blower relay circuits, refer to the

Heating & A/C catagory. For all other FCM DTCs, refer to the
symptom list in the related catagory.
Perform BODY VERIFICATION TEST - VER 1.

No

→ Go To 5

575

HEATING & A/C

TEST

ACTION

APPLICABILITY

5

CAUTION: The evaporator temperature must be above 12.7°C (55°F) and the
work area ambient temperature must be above 21.1°C (70°F) to test the A/C
system operation.
NOTE: Active codes must be resolved before diagnosing stored codes.
NOTE: Anytime a DTC becomes active, or a Cooldown Test fault message,
Actuator Circuit Test fault message, or HVAC Door Recalibration fault
message is displayed, proceed to the conclusion question.
NOTE: If multiple codes appear, diagnose those that relate to a short circuit
first.
Start the engine.
Press the A/C - Heater Control power switch on.
Turn the mode select control to the panel position.
Verify that the front blower motor and, if equipped, rear blower motor operates
correctly in all speeds from each control. Diagnose and repair all blower related faults
before proceeding with this test.
Turn the front blower motor control to the high speed position.
NOTE: Before actuating the AC Cooldown Test, verify that the A/C compres-
sor is not running. If the compressor is running, turn the A/C off and allow
the evaporator to warm up before proceeding with the test.
With the DRBIII

t in HVAC, System Tests, actuate the AC Cooldown Test.

Turn the front blower motor control to the low speed position.
If equipped, turn the rear blower motor control to the rear position.
Set the passenger blend control to the full cold position.
If equipped, set the zone/driver blend control to the full cold position.
If equipped, on the Rear Blower Rear Control, set the rear blend/mode control to the
full cold position.
Monitor the DRBIII

t for active HVAC DTCs while performing the following test

steps.
Turn the mode select control to the defrost position, wait 30 seconds, and then turn
it back to the panel position.
Press the recirculation mode switch on, wait 30 seconds, and then press it off.
Press the A/C mode switch on, wait 30 seconds, and then press it off.
Press the rear window defogger switch on, wait 30 seconds, and then press it off.
Move the passenger blend control from full cold to full hot, wait 30 seconds, and then
move it back to full cold.
If equipped, move the zone/driver blend control from full cold to full hot, wait 30
seconds, and then move it back to full cold.
If equipped, on the Rear Blower Rear Control, move the rear blend/mode control from
full cold to full hot, wait 30 seconds, and then move it back to full cold.
With the DRBIII

t in HVAC, System Tests, actuate the Actuator Circuit Test.

With the DRBIII

t in HVAC, System Tests, actuate the HVAC Door Recalibration

Test.
Does the DRBIII

t display any active HVAC DTC(s) or System Tests fault message(s)?

All

Yes

→ Return to the symptom list and choose the symptom(s).

Perform BODY VERIFICATION TEST - VER 1.

No

→ Go To 6

6

With the DRBIII

t, read PCM/ECM DTCs.

Are any HVAC related DTCs present?

All

Yes

→ Refer to the Powertrain Diagnostic Procedures Manual for the

related symptom(s).
Perform BODY VERIFICATION TEST - VER 1.

No

→ Recheck the climate control system performance. Refer to Service

Information for additional information.
Perform BODY VERIFICATION TEST - VER 1.

576

HEATING & A/C

*HVAC SYSTEM TEST - MTC —

Continued

Symptom:

*REAR A/C - HEATER CONTROL ILLUMINATION INOPERATIVE -
MTC

POSSIBLE CAUSES

CHECK FOR HVAC DTCS

CHECK FOR BCM DTCS

INOPERATIVE BULB

GROUND CIRCUIT OPEN

REAR BLOWER REAR CONTROL SWITCH

PANEL LAMPS DRIVER CIRCUIT OPEN

BODY CONTROL MODULE - PANEL LAMPS DRIVER OPEN

TEST

ACTION

APPLICABILITY

1

Turn the ignition on.
With the DRBIII

t, read HVAC DTCs.

Does the DRBIII

t display any HVAC DTCs?

All

Yes

→ Return to the symptom list and choose the symptom(s).

Perform BODY VERIFICATION TEST - VER 1.

No

→ Go To 2

2

Turn the ignition on.
With the DRBIII

t, read the BCM DTCs.

Does DRBIII

t display Headlamp Switch: Mismatch; STG; Open; or Panel Dim

Output Short?

All

Yes

→ Refer to symptoms Headlamp Switch Mismatch, Headlamp

Switch Shorted To Ground, and Headlamp Switch Open in the
Exterior Lighting catagory. Refer to symptom Panel Dimming
Output Short in the Instrument Cluster catagory.
Perform BODY VERIFICATION TEST - VER 1.

No

→ Go To 3

3

Turn the ignition off.
Remove the bulb from the Rear Blower Rear Control Switch.
NOTE: Hold the bulb in front of a lamp to see the filament.
Inspect the bulb.
Is the bulb Ok?

All

Yes

→ Go To 4

No

→ Replace the bulb.

Perform BODY VERIFICATION TEST - VER 1.

577

HEATING & A/C

TEST

ACTION

APPLICABILITY

4

Turn the ignition off.
Rotate the Panel Lamps Dimmer switch to the off position.
Disconnect the Rear Blower Rear Control Switch C2 harness connector.
Turn the Headlamp switch on.
Measure the voltage of the Panel Lamps Driver circuit while rotating the Panel
Lamps Dimmer switch from the off position to the full brightness position.
Does the voltage change from approximately 2.5 volts to 11.5 volts?

All

Yes

→ Go To 5

No

→ Go To 6

5

Turn the Headlamp switch off.
Turn the ignition off.
Disconnect the Rear Blower Rear Control Switch C2 harness connector.
Measure the resistance of the Ground circuit between the Rear Blower Rear Control
switch C2 harness connector and ground.
Is the resistance below 5 ohms?

All

Yes

→ Replace the Rear Blower Rear Control Switch in accordance with

the Service Information.
Perform BODY VERIFICATION TEST - VER 1.

No

→ Repair the Ground circuit for an open.

Perform BODY VERIFICATION TEST - VER 1.

6

Turn the ignition off.
Disconnect the Rear Blower Rear Control Switch C2 harness connector.
Disconnect the Body Control Module C3 harness connector.
Measure the resistance of the Panel Lamps Driver circuit between the Rear Blower
Rear Control Switch C2 harness connector and the Body Control Module C3 harness
connector.
Is the resistance below 5 ohms?

All

Yes

→ Replace the Body Control Module in accordance with the Service

Information.
Perform BODY VERIFICATION TEST - VER 1.

No

→ Repair the Panel Lamps Driver circuit for an open.

Perform BODY VERIFICATION TEST - VER 1.

578

HEATING & A/C

*REAR A/C - HEATER CONTROL ILLUMINATION INOPERATIVE - MTC
—

Continued