Chrysler Voyager. Manual — part 289

Symptom:

*REAR BLOWER MOTOR SPEEDS INCORRECT - MTC

POSSIBLE CAUSES

REAR BLOWER REAR CONTROL SWITCH

REAR BLOWER MOTOR DRIVER CIRCUIT(S) SHORTED TO GROUND

A/C - HEATER CONTROL MODULE

REAR BLOWER REAR CONTROL SWITCH

REAR BLOWER MOTOR DRIVER CIRCUIT(S) SHORTED TO VOLTAGE

REAR BLOWER MOTOR FRONT CONTROL FEED CIRCUIT SHORTED TO VOLTAGE

REAR BLOWER DRIVER CKT(S) SHORTED TO REAR BLOWER FRONT CONTROL FEED CKT

REAR BLOWER MOTOR DRIVER CIRCUITS SHORTED TOGETHER

A/C - HEATER CONTROL MODULE

REAR BLOWER MOTOR DRIVER CIRCUIT(S) OPEN

REAR BLOWER MOTOR RESISTOR BLOCK

TEST

ACTION

APPLICABILITY

1

Turn the Rear Blower switch on the A/C - Heater Control Module off.
Turn the ignition on.
Turn the Power switch on the A/C - Heater Control Module on.
Does the rear blower run?

All

Yes

→ Go To 2

No

→ Go To 4

2

Turn the Rear Blower switch on the A/C - Heater Control Module off.
Turn the Power switch on the A/C - Heater Control Module off.
Turn the ignition off.
Disconnect the Rear Blower Rear Control Switch C1 harness connector.
Turn the ignition on.
Turn the Power switch on the A/C - Heater Control Module on.
Does the rear blower run?

All

Yes

→ Go To 3

No

→ Replace the Rear Blower Rear Control Switch in accordance with

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

583

HEATING & A/C

TEST

ACTION

APPLICABILITY

3

Turn the ignition off.
Disconnect the Rear Blower Front Control Switch harness connector.
Disconnect the Rear Blower Rear Control Switch C1 harness connector.
Measure the resistance between ground and each of the Rear Blower Motor Driver
circuits (Low, Medium, and High) in the Rear Blower Front Control Switch harness
connector.
Is the resistance below 10K ohms on any of the circuits?

All

Yes

→ Repair all Rear Blower Motor Driver circuits with a resistance

below 10K ohms for a short to ground.
Perform BODY VERIFICATION TEST - VER 1.

No

→ Replace the A/C - Heater Control Module in accordance with the

Service Information.
Perform BODY VERIFICATION TEST - VER 1.

4

Turn the Rear Blower switch on the A/C - Heater Control Module off.
Turn the Power switch on the A/C - Heater Control Module off.
Turn the ignition off.
Disconnect the Rear Blower Rear Control Switch C1 harness connector.
Turn the ignition on.
Turn the Power switch on the A/C - Heater Control Module on.
Turn the Rear Blower switch on the A/C - Heater Control Module to the Low,
Medium, and High speed positions while listening for the rear blower motor to
change speed accordingly.
Does the rear blower speed change accordingly?

All

Yes

→ Replace the Rear Blower Rear Control Switch in accordance with

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

No

→ Go To 5

5

Turn the Power switch on the A/C - Heater Control Module off.
Turn the ignition off.
Disconnect the Rear Blower Front Control Switch harness connector.
Disconnect the Rear Blower Rear Control Switch C1 harness connector.
Turn the ignition on.
Turn the Power switch on the A/C - Heater Control Module on.
NOTE: The test light must illuminate brightly. Compare the brightness to
that of a direct connection to the battery.
Using a 12-volt test light connect to ground, back probe each of the Rear Blower
Motor Driver circuits (Low, Medium, and High) in the Rear Blower Front Control
Switch harness connector and in the Rear Blower Rear Control Switch C1 harness
connector.
Does the test light illuminate brightly on each circuit?

All

Yes

→ Go To 6

No

→ Go To 10

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*REAR BLOWER MOTOR SPEEDS INCORRECT - MTC —

Continued

TEST

ACTION

APPLICABILITY

6

Turn the Power switch on the A/C - Heater Control Module off.
Turn the ignition off.
Disconnect the Rear Blower Front Control Switch harness connector.
Disconnect the Rear Blower Rear Control Switch C1 harness connector.
Turn the ignition on
Measure the voltage of each of the Rear Blower Motor Driver circuits (Low, Medium,
and High).
Is there voltage present on any of the circuits?

All

Yes

→ Repair all Rear Blower Motor Driver circuits with voltage present

for a short to voltage.
Perform BODY VERIFICATION TEST - VER 1.

No

→ Go To 7

7

Turn the Power switch on the A/C - Heater Control Module off.
Turn the ignition off.
Disconnect the Rear Blower Front Control Switch harness connector.
Disconnect the Rear Blower Rear Control Switch C1 harness connector.
Turn the ignition on
Measure the voltage of the Rear Blower Motor Front Control Feed circuit.
Is there any voltage present?

All

Yes

→ Repair the Rear Blower Motor Front Control Feed circuit for a

short to voltage.
Perform BODY VERIFICATION TEST - VER 1.

No

→ Go To 8

8

Turn the ignition off.
Disconnect the Rear Blower Front Control Switch harness connector.
Disconnect the Rear Blower Rear Control Switch C1 harness connector.
Measure the resistance between the Rear Blower Motor Front Control Feed circuit
and each of the Rear Blower Motor Driver circuits (Low, Medium, and High).
Is the resistance below 10K ohms on any of the circuits?

All

Yes

→ Repair all Rear Blower Motor Driver circuits with a resistance

below 10K ohms for a short to the Rear Blower Motor Front
Control Feed circuit.
Perform BODY VERIFICATION TEST - VER 1.

No

→ Go To 9

9

Turn the ignition off.
Disconnect the Rear Blower Front Control Switch harness connector.
Disconnect the Rear Blower Rear Control Switch C1 harness connector.
Disconnect the Rear Blower Motor Resistor Block harness connector.
Measure the resistance between the Rear Blower Motor Low circuit and the Rear
Blower Motor Medium and High circuits.
Measure the resistance between the Rear Blower Motor Medium circuit and the Rear
Blower Motor High circuit.
Is the resistance below 10K ohms between any of the circuits?

All

Yes

→ Repair the shorted Rear Blower Motor Driver circuits.

Perform BODY VERIFICATION TEST - VER 1.

No

→ Replace the A/C - Heater Control Module in accordance with the

Service Information.
Perform BODY VERIFICATION TEST - VER 1.

585

HEATING & A/C

*REAR BLOWER MOTOR SPEEDS INCORRECT - MTC —

Continued

TEST

ACTION

APPLICABILITY

10

Turn the ignition off.
Disconnect the Rear Blower Front Control Switch harness connector.
Disconnect the Rear Blower Rear Control Switch C1 harness connector.
Disconnect the Rear Blower Motor Resistor Block harness connector.
Measure the resistance of each of the Rear Blower Motor Driver circuits (Low,
Medium, and High) between the Rear Blower Motor Resistor Block harness connec-
tor and the Rear Blower Motor Front Control Switch harness connector.
Measure the resistance of each of the Rear Blower Motor Driver circuits (Low,
Medium, and High) between the Rear Blower Motor Resistor Block harness connec-
tor and the Rear Blower Rear Control Switch C1 harness connector.
Is the resistance below 5.0 ohms on each of the circuits?

All

Yes

→ Replace the Rear Blower Motor Resistor Block in accordance with

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

No

→ Repair all Rear Blower Motor Driver circuit(s) with a resistance

above 5 ohms for an open.
Perform BODY VERIFICATION TEST - VER 1.

586

HEATING & A/C

*REAR BLOWER MOTOR SPEEDS INCORRECT - MTC —

Continued