Diagnosis Procedure

1. Turn ignition switch OFF.
2. Check 15A fuses [Nos. 17 and 27, located in fuse block (J/B)].
   NOTE: Refer to appropriate wiring information .

Is the inspection result normal?

YES

GO TO 2.

NO

Replace the blown fuse after repairing the affected circuit.

1. Disconnect front blower motor connector.
2. Turn ignition switch ON.
3. Check voltage between front blower motor harness connector and ground.

   +		-		Voltage (Approx.)
   Front blower motor
   Connector	Terminal
   M112	4	Ground		Battery voltage

Is the inspection result normal?

YES

GO TO 3.

NO

GO TO 6.

1. Turn ignition switch OFF.
2. Check continuity between front blower motor harness connector and ground.

   Front blower motor		--		Continuity
   Connector	Terminal
   M112	1	Ground		Yes

Is the inspection result normal?

YES

GO TO 4.

NO

Repair harness or connector.

1. Disconnect A/C auto amp. connector.
2. Check continuity between front blower motor harness connector and A/C auto amp. harness connector.

   Front blower motor		A/C auto amp.		Continuity
   Connector	Terminal	Connector	Terminal
   M112	3	M50	18	Yes

Is the inspection result normal?

YES

GO TO 5.

NO

Repair the harness or connector.

1. Reconnect front blower motor connector and A/C auto amp. connector.
2. Turn ignition switch ON.
3. Operate MODE switch to set air outlet to VENT.
4. Change fan speed from Lo to Hi, and check duty ratios between front blower motor harness connector and ground by using an oscilloscope.
   NOTE: Calculate drive signal duty ratio as shown in the figure.

   T2 = Approx. 1.6 ms

   Courtesy of NISSAN NORTH AMERICA, INC.

   Front blower motor		Condition	Duty ratio (Approx.)
   Connector	Terminal	Fan speed (manual) VENT mode
   M112	3	1st	25 %
   		2nd	33 %
   		3rd	41 %
   		4th	51 %
   		5th	61 %
   		6th	69 %
   		7th	81 %

Is the inspection result normal?

YES

Replace front blower motor. Refer to Removal and Installation .

NO

Replace A/C auto amp. Refer to Removal and Installation .

1. Turn ignition switch OFF.
2. Check continuity between fuse block (J/B) harness connector and ground.

   Fuse block (J/B)		--	Continuity
   Connector	Terminal
   M68	13R	Ground	Yes

Is the inspection result normal?

YES

GO TO 7.

NO

Repair harness or connector.

Check front blower motor relay. Refer to Component Inspection (Front Blower Motor Relay) .

Is the inspection result normal?

YES

Repair harness or connector between front blower motor and fuse block (J/B).

NO

Replace front blower motor relay.