Nissan Frontier D22. Manual - part 829

MTC-38

TROUBLE DIAGNOSIS

3. 

CHECK BLOWER MOTOR POWER SUPPLY CIRCUIT

1.

Disconnect blower motor harness connector.

2.

Check voltage between blower motor harness connector M62
terminal 1 and ground.

Does battery voltage exist?

Yes

>> GO TO 4.

No

>> Check the following.

●

If NG, repair harness or connector.

–

Harness for open between blower motor and fuse
block (J/B).

–

Harness connectors M27 and M62

4. 

CHECK BLOWER MOTOR GROUND CIRCUIT

1.

Disconnect blower motor harness connector.

2.

Turn fan control knob to 4-speed.

3.

Check continuity between blower motor harness connector M62
terminal 2 (L/W) and ground.

OK or NG

OK

>> GO TO 5.

NG

>> Check the following. If NG, repair harness or connector.

●

Harness for open between blower motor and ground.

●

Harness connectors M57 and M62

5. 

CHECK BLOWER MOTOR

1.

Disconnect blower motor harness connector.

2.

Apply 12 volts to blower motor terminal 1 and ground to blower
motor terminal 2.

Does blower motor rotate?

Yes

>> Reconnect blower motor connector and go to 

MTC-37,

"Trouble Diagnosis Procedure for Blower Motor"

 .

No

>> Replace blower motor.

AHA485A

Continuity should exist.

WJIA0281E

AHA455A

TROUBLE DIAGNOSIS

MTC-39

C

D

E

F

G

H

I

K

L

M

A

B

MTC

6. 

CHECK FAN RESISTOR

1.

Disconnect fan resistor harness connector M61.

2.

Check resistance between fan resistor terminals.

OK or NG

OK

>> GO TO 7.

NG

>> Replace fan resistor.

7. 

CHECK FAN SWITCH

Disconnect fan switch harness connector M57 and check continuity
between terminals at each fan switch position.

OK or NG

OK

>> GO TO 8.

NG

>> Replace fan switch.

Terminal No.

Resistance

Ω

(Approx.)

(+)

(–)

1

2

0.2 - 0.3

3

0.8 - 1.0

4

2.0 - 2.4

AHA458A

AHA456A

AHA457A

MTC-40

TROUBLE DIAGNOSIS

8. 

CHECK FAN SWITCH GROUND

1.

Disconnect fan switch harness connector M57.

2.

Check continuity between fan switch harness connector terminal
6 and ground.

OK or NG

OK

>> Check the following.

●

If NG, repair harness or connectors.

–

Harness connectors M57, M61 and M62

–

Harness for open or short between blower motor and
fan switch, fan resistor

NG

>> Repair harness or connector.

9. 

REPLACE FUSE

1.

Replace fuse(s).

2.

Activate the blower motor system.

Do the fuses blow when the front blower motor is activated?

Yes

>> GO TO 10.

No

>> INSPECTION END

10. 

CHECK BLOWER MOTOR POWER SUPPLY CIRCUIT FOR A SHORT

1.

Disconnect battery cable and blower motor harness connector M62.

2.

Check continuity between front blower motor harness connector M62 terminal 1 (L) and ground.

Does continuity exist?

Yes

>> Check the following. If NG, repair harness or connector.

●

Harness connectors M27 and M62

●

Harness for short between blower motor and fuse block (J/B).

No

>> Check front blower motor. Refer to 

MTC-41, "Blower Motor"

 . If necessary, clear intake unit. If OK,

replace front blower motor.

Continuity should exist.

AHA078A

WHA311

TROUBLE DIAGNOSIS

MTC-41

C

D

E

F

G

H

I

K

L

M

A

B

MTC

ELECTRICAL COMPONENTS INSPECTION
Fan Switch

Check continuity between terminals at each switch position.

Blower Motor

Confirm smooth rotation of the blower motor.

●

Check that there are no foreign particles inside the intake unit.

Fan Resistor

Check resistance between terminals.

AHA456A

AHA457A

AHA547A

Terminal No.

Resistance

Ω

(Approx.)

(+)

(–)

1

2

0.2 - 0.3

3

0.8 - 1.0

4

2.0 - 2.4

AHA458A