Ins INFINITI QX56 2004 Factory Service Manual

ATC-76
TROUBLE DIAGNOSIS
Revision: August 20072004 QX56
Intake Door Motor CircuitEJS002CG
SYMPTOM:

Intake door does not change.

Intake door motor does not operate normally.
INSPECTION FLOW
*1ATC-56, "Operational Check (Front)"*2AT C - 5 3 , "A/C System Self-diagno-
sis Function"
*3AT C - 5 5 , "SELF-DIAGNOSIS CODE
CHART"
WJIA0767E

TROUBLE DIAGNOSIS
ATC-79
C
D
E
F
G
H
I
K
L
MA
B
AT C
Revision: August 20072004 QX56
Defroster Door Motor CircuitEJS002CH
SYMPTOM:

Defroster door does not change.

Defroster door motor does not operate normally.
INSPECTION FLOW
*1ATC-56, "Operational Check
(Front)"*2AT C - 5 3 , "A/C System Self-diagnosis
Function"*3AT C - 5 5 , "SELF-DIAGNOSIS CODE
CHART"
LJIA0062E

TROUBLE DIAGNOSIS
ATC-81
C
D
E
F
G
H
I
K
L
MA
B
AT C
Revision: August 20072004 QX56
DIAGNOSTIC PROCEDURE FOR DEFROSTER DOOR MOTOR
1. CHECK RESULT FROM FRONT AIR CONTROL SELF-DIAGNOSIS
Self-diagnosis code 62 is present. Refer to ATC-53, "
A/C System Self-diagnosis Function" .
YES or NO
YES >> GO TO 2.
NO >> GO TO 3.
2. CHECK POWER SUPPLY CIRCUIT FOR DEFROSTER DOOR MOTOR
1. Turn ignition switch OFF.
2. Disconnect front air control connector M49 and defroster door
motor connector M144.
3. Check continuity between front air control harness connector
M49 terminal 19 (LG) and defroster door motor harness connec-
tor M144 terminal 1 (LG) and between front air control harness
connector M49 terminal 20 (P/B) and defroster door motor con-
nector M144 terminal 6 (P/B).
OK or NG
OK >> Replace defroster door motor. Refer to ATC-150, "Removal and Installation" .
NG >> Repair or replace harness as necessary.
3. CHECK PBR REFERENCE SIGNAL VOLTAGE
1. Disconnect defroster door motor harness connector M144.
2. Turn ignition switch ON.
3. Check voltage between defroster door motor harness connector
M144 terminal 3 (Y) and ground.
OK or NG
OK >> GO TO 5.
NG >> GO TO 4.
4. CHECK PBR REFERENCE VOLTAGE CIRCUIT BETWEEN DEFROSTER DOOR MOTOR AND FRONT
AIR CONTROL
1. Turn ignition switch OFF.
2. Disconnect front air control connector M49.
3. Check continuity between defroster door motor harness connec-
tor M144 terminal 3 (Y) and front air control harness connector
M49 terminal 2 (Y).
OK or NG
OK >> Replace front air control. Refer to ATC-135, "FRONT
AIR CONTROL" .
NG >> Repair or replace harness as necessary.19 - 1 : Continuity should exist.
20 - 6 : Continuity should exist.
WJIA0553E
3 - Ground : Approx. 5V
WJIA0554E
3 - 2 : Continuity should exist.
WJIA0555E

ATC-82
TROUBLE DIAGNOSIS
Revision: August 20072004 QX56
5. CHECK PBR GROUND REFERENCE CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect front air control connector M49.
3. Check continuity between defroster door motor harness connec-
tor M144 terminal 2 (P) and front air control harness connector
M49 terminal 15 (P).
OK or NG
OK >> GO TO 6.
NG >> Repair or replace harness as necessary.
6. CHECK PBR FEEDBACK SIGNAL
1. Reconnect front air control connector and defroster door motor
connector.
2. Turn ignition switch ON.
3. Check voltage between front air control harness connector M49
terminal 25 (LG/B) and ground.
4. Change mode between floor, defroster, and panel.
OK or NG
OK >> Replace front air control. Refer to ATC-135, "FRONT
AIR CONTROL" .
NG >> GO TO 7.
7. CHECK PBR FEEDBACK CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect defroster door motor connector M144 and front air
control connector M49.
3. Check continuity between defroster door motor harness connec-
tor M144 terminal 4 (LG/B) and front air control harness connec-
tor M49 terminal 25 (LG/B).
OK or NG
OK >> Replace defroster door motor. Refer to ATC-150,
"Removal and Installation" .
NG >> Repair or replace harness as necessary.2 - 15 : Continuity should exist.
WJIA0556E
25 - Ground : Approx. 0 - 5V
WJIA0770E
4 - 25 : Continuity should exist.
WJIA0558E

TROUBLE DIAGNOSIS
ATC-83
C
D
E
F
G
H
I
K
L
MA
B
AT C
Revision: August 20072004 QX56
Front Blower Motor CircuitEJS002CI
SYMPTOM:

Blower motor operation is malfunctioning.
INSPECTION FLOW
*1 .AT C - 5 6 , "Operational Check
(Front)"
*2AT C - 5 3 , "A/C System Self-diagnosis
Function"
*3AT C - 5 5 , "SELF-DIAGNOSIS CODE
CHART"
*4ATC-85, "DIAGNOSTIC PROCE-
DURE FOR BLOWER MOTOR"
*5EC-410, "DTC P1217 ENGINE
OVER TEMPERATURE"
WJIA0771E

ATC-88
TROUBLE DIAGNOSIS
Revision: August 20072004 QX56
10. REPLACE FUSES
1. Replace fuses.
2. Activate the front blower motor.
3. Do fuses blow?
YES or NO
YES >> GO TO 11.
NO >> Inspection End.
11 . CHECK FRONT BLOWER MOTOR POWER SUPPLY CIRCUIT FOR SHORT
1. Turn ignition switch OFF.
2. Disconnect variable blower control connector M122.
3. Check continuity between variable blower control harness con-
nector M122 terminal 1 (W/L) and ground.
OK or NG
OK >> GO TO 12.
NG >> Repair harness or connector.
12. CHECK VARIABLE BLOWER CONTROL SIGNAL CIRCUIT
1. Disconnect front air control connector M49.
2. Check continuity between front air control harness connector
M49 terminal 13 (G/R) and variable blower control harness con-
nector M122 terminal 2 (G/R).
OK or NG
OK >> Check blower motor, if OK replace variable blower con-
trol. Refer to ATC-89, "
Front Blower Motor" .
NG >> Repair harness or connector.1 - Ground. : Continuity should not exist.
WJIA0788E
13 - 2 : Continuity should exist.
WJIA0785E

TROUBLE DIAGNOSIS
ATC-89
C
D
E
F
G
H
I
K
L
MA
B
AT C
Revision: August 20072004 QX56
COMPONENT INSPECTION
Front Blower Motor Relay
Check continuity between terminals by supplying 12 volts and
ground to coil side terminals of relay.
Front Blower Motor
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.
LJIA0068E
WJIA0895E

ATC-90
TROUBLE DIAGNOSIS
Revision: August 20072004 QX56
Rear Blower Motor CircuitEJS002CJ
SYMPTOM:

Blower motor operation is malfunctioning.
INSPECTION FLOW
*1AT C - 5 9 , "Operational Check (Rear)"*2AT C - 9 9 , "Rear Fan Switch (Front)"*3AT C - 3 5 , "SYMPTOM TABLE"
WJIA0791E

ATC-92
TROUBLE DIAGNOSIS
Revision: August 20072004 QX56
1. CHECK REAR BLOWER MOTOR OPERATION
Blower motor rotates normally when rear fan switch (front) is set at 1 - 4 speed.
OK or NG
OK >> GO TO 2.
NG >> Refer to AT C - 9 3 , "
Trouble Diagnosis Procedure For Rear Blower Motor (1 - 4 Speed)" .
2. CHECK REAR FAN SWITCH (FRONT)
Refer to ATC-99, "
Rear Fan Switch (Front)" .
OK or NG
OK >> GO TO 3.
NG >> Replace rear fan switch (front). Refer to ATC-135, "
FRONT AIR CONTROL"
3. CHECK REAR FAN SWITCH (REAR)
Refer to ATC-99, "
Rear Fan Switch (Rear)" .
OK or NG
OK >> GO TO 4.
NG >> Replace rear fan switch (rear). Refer to ATC-135, "
REAR AIR CONTROL" .
4. CHECK CIRCUIT CONTINUITY
1. Turn ignition switch OFF.
2. Disconnect rear fan switch (front) connector M52 and rear fan
switch (rear) (Rear air control) connector R208.
3. Check voltage between rear fan switch (front) harness connec-
tor M52 terminal 2 (BR) and rear fan switch (rear) (Rear air con-
trol) harness connector R208 terminal 10 (BR).
OK or NG
OK >> Inspection End.
NG >> Repair harness or connector.2 - 10 : Continuity should exist.WJIA0794E

TROUBLE DIAGNOSIS
ATC-93
C
D
E
F
G
H
I
K
L
MA
B
AT C
Revision: August 20072004 QX56
Trouble Diagnosis Procedure For Rear Blower Motor (1 - 4 Speed)
SYMPTOM:

Rear blower motor does not rotate when rear fan switch (front) is set at 1 - 4 speed.
Inspection Flow
*1AT C - 5 9 , "Operational Check (Rear)"*2AT C - 9 3 , "Trouble Diagnosis Proce-
dure For Rear Blower Motor (1 - 4
Speed)"
*3ATC-35, "SYMPTOM TABLE"
WJIA0795E