Nissan Titan. Manual - part 427

BLOWER MOTOR CONTROL SYSTEM

HAC-213

< DTC/CIRCUIT DIAGNOSIS >

[MANUAL A/C (TYPE 2)]

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1. Turn ignition switch OFF.

2. Disconnect front blower motor relay.

3. Check voltage between front blower motor relay harness con-

nector M107 terminal 5 and ground.

Is the inspection result normal?

YES

>> GO TO 4.

NO

>> Repair harness or connector.

4.

CHECK FRONT BLOWER MOTOR RELAY

Turn ignition switch OFF.

Check front blower motor relay. Refer to 

HAC-215, "Front Blower Motor Component Inspection"

.

Is the inspection result normal?

YES

>> GO TO 5.

NO

>> Replace front blower motor relay.

5.

CHECK FRONT BLOWER MOTOR RELAY (SWITCH SIDE) CIRCUIT FOR OPEN

Check continuity between front blower motor relay harness connec-

tor M107 terminal 3 and front blower motor harness connector M62

terminal 2.

Is the inspection result normal?

YES

>> GO TO 6.

NO

>> Repair harness or connector.

6.

CHECK VARIABLE BLOWER CONTROL POWER SUPPLY CIRCUIT FOR OPEN

1. Disconnect variable blower control harness connector.

2. Check continuity between front blower motor relay harness con-

nector M107 (A) terminals 3 and variable blower control harness

connector M121 (B) terminal 1.

Is the inspection result normal?

YES

>> GO TO 7.

NO

>> Repair harness or connector.

7.

CHECK VARIABLE BLOWER CONTROL SIGNAL CIRCUIT

1. Disconnect front air control connector.

2. Check continuity between front air control harness connector

M177 (B) terminal 40 and variable blower control harness con-

nector M121 (A) terminal 2.

Is the inspection result normal?

YES

>> GO TO 8.

NO

>> Repair harness or connector.

8.

CHECK FRONT BLOWER MOTOR RELAY (COIL SIDE) POWER SUPPLY

5 - Ground

: Battery voltage

WJIA1886E

3 - 2

: Continuity should exist.

WJIA1360E

3 - 1

: Continuity should exist.

AWIIA1387ZZ

40 - 2

: Continuity should exist.

AWIIA0537ZZ

HAC-214

< DTC/CIRCUIT DIAGNOSIS >

[MANUAL A/C (TYPE 2)]

BLOWER MOTOR CONTROL SYSTEM

1. Turn ignition switch ON.

2. Check voltage between front blower motor relay harness con-

nector M107 terminal 1 and ground.

Is the inspection result normal?

YES

>> GO TO 9.

NO

>> Repair front blower motor ground circuit or connector.

9.

REPLACE FUSES

1. Replace fuses.

2. Activate the front blower motor.
Does the fuse blow?

YES

>> GO TO 10.

NO

>> Inspection End.

10.

CHECK FRONT BLOWER MOTOR POWER SUPPLY CIRCUIT FOR SHORT

1. Turn ignition switch OFF.

2. Disconnect front blower motor connector and variable blower

control connector.

3. Check continuity between variable blower control harness con-

nector M121 terminal 1 and ground.

Is the inspection result normal?

YES

>> GO TO 11.

NO

>> Repair harness or connector.

11.

CHECK VARIABLE BLOWER CONTROL SIGNAL CIRCUIT

1. Disconnect front air control connector.

2. Check continuity between front air control harness connector

M177 (B) terminal 40 and variable blower control harness con-

nector M121 (A) terminal 2.

Is the inspection result normal?

YES

>> GO TO 12.

NO

>> Repair harness or connector.

12.

CHECK FRONT BLOWER MOTOR

Check front blower motor. Refer to 

HAC-211, "Front Blower Motor Component Function Check"

.

Is the inspection result normal?

YES

>> GO TO 13.

NO

>> Replace front blower motor. Refer to 

VTL-12, "Removal and Installation"

.

13.

CHECK BLOWER MOTOR GROUND CIRCUIT

1 - Ground

: Battery voltage

AWIIA1388ZZ

1 - Ground

: Continuity should not exist.

AWIIA0539ZZ

40 - 2

: Continuity should exist.

AWIIA0537ZZ

BLOWER MOTOR CONTROL SYSTEM

HAC-215

< DTC/CIRCUIT DIAGNOSIS >

[MANUAL A/C (TYPE 2)]

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G

H

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A

B

HAC

N

O

P

Check continuity between front blower motor harness connector

M62 (B) terminal 1 and variable blower control harness connector

M121 (A) terminal 3.

Is the inspection result normal?

YES

>> GO TO 14.

NO

>> Repair harness or connector.

14.

CHECK VARIABLE BLOWER CONTROL GROUND CIRCUIT

Check continuity between variable blower control harness connector

M121 terminal 4 and ground.

Is the inspection result normal?

YES

>> Replace variable blower control. Refer to 

VTL-22,

"Removal and Installation"

.

NO

>> Repair harness or connector.

Front Blower Motor Component Inspection

INFOID:0000000009882590

COMPONENT INSPECTION 

Check continuity between terminals by supplying 12 volts and

ground to coil side terminals of relay.

Front Blower Motor

1 - 3

: Continuity should exist.

AWIIA0540ZZ

4 - Ground

: Continuity should exist.

AWIIA0541ZZ

WJIA1401E

HAC-216

< DTC/CIRCUIT DIAGNOSIS >

[MANUAL A/C (TYPE 2)]

BLOWER MOTOR CONTROL SYSTEM

Confirm smooth rotation of the blower motor.

• Ensure that there are no foreign particles inside the blower unit.

• Apply 12 volts to terminal 2 and ground to terminal 1 and verify that

the motor operates freely and quietly.

WJIA1508E