2006 INFINITI QX56 blower motor

TROUBLE DIAGNOSISATC-101
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Revision: November 2009 2006 QX56
Rear Blower Motor CircuitEJS003XT
SYMPTOM:

Blower motor operation is malfunctioning.
INSPECTION FLOW
*1AT C - 6 0 , "Operational Check (Rear)"*2ATC-102, "Rear Blower Switch
(Rear) Circuit"
*3 ATC-39, "SYMPTOM TABLE"
WJIA1266E

ATC-102
TROUBLE DIAGNOSIS
Revision: November 20092006 QX56
SYSTEM DESCRIPTION
Component Parts
Rear blower speed control system components are:

Front air control

Rear blower switch (front)

Rear air control

Rear blower motor resistor

Rear blower motor

Rear blower motor relay
System Operation
Rear Blower Control
When the rear blower control dial (front) is in the OFF position, the rear blower motor cannot operate.
When the rear blower control dial (front) is in the REAR position, it allows the rear blower switch (rear) to con-
trol the rear blower motor speed. In any other position (1-4), the rear blower switch (front) controls the rear
blower motor speed regardless of the rear blower switch (rear) position.
DIAGNOSTIC PROCEDURE FOR REAR BLOWER MOTOR
Rear Blower Switch (Rear) Circuit
SYMPTOM:

Rear blower motor does not rotate when rear blower switch (front) is set to REAR position and the rear
blower switch (rear) is set at 1-4 speed.
1. CHECK REAR BLOWER MOTOR OPERATION
Blower motor rotates normally when rear blower control dial (front) is set at 1 - 4 speed.
OK or NG
OK >> GO TO 2.
NG >> Refer to ATC-104, "
Trouble Diagnosis Procedure For Rear Blower Motor (1 - 4 Speed)" .
2. CHECK REAR BLOWER SWITCH (FRONT)
Refer to AT C - 11 0 , "
Rear Blower Switch (Front)" .
OK or NG
OK >> GO TO 3.
NG >> Replace rear blower switch (front). Refer to ATC-144, "
FRONT AIR CONTROL" .
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ATC-104
TROUBLE DIAGNOSIS
Revision: November 20092006 QX56
Trouble Diagnosis Procedure For Rear Blower Motor (1 - 4 Speed)
SYMPTOM:

Rear blower motor does not rotate when rear blower control dial (front) is set at 1 - 4 speed.
Inspection Flow
*1 .ATC-60, "Operational Check
(Rear)"
*2ATC-104, "Trouble Diagnosis Proce-
dure For Rear Blower Motor (1 - 4
Speed)"
*3AT C - 3 9 , "SYMPTOM TABLE"
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TROUBLE DIAGNOSISATC-105
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Revision: November 2009 2006 QX56
1. DIAGNOSTIC PROCEDURE
Blower motor rotates normally at each speed.
OK or NG
OK >> Inspection End.
NG >> 1. Does not rotate at any speed, GO TO 2. 2. Does not rotate at 1 - 3 speed, GO TO 13.
3. Does not rotate at 4 speed, GO TO 18.
2. CHECK FUSES
Check 15A fuses [Nos. 10 and 11, located in the fuse block (J/B)]. Refer to PG-76, "
FUSE BLOCK-JUNCTION
BOX (J/B)" .
OK or NG
OK >> GO TO 3.
NG >> GO TO 8.
3. CHECK REAR BLOWER MOTOR POWER SUPPLY
1. Turn ignition switch OFF.
2. Disconnect rear blower motor connector.
3. Select any rear blower speed except OFF.
4. Turn ignition switch ON.
5. Check voltage between rear blower motor harness connector B134 terminal 2 and ground.
OK or NG
OK >> GO TO 11.
NG >> GO TO 4.
4. CHECK REAR BLOWER MOTOR RELAY
Turn ignition switch OFF.
Refer to AT C - 11 0 , "
Rear Blower Motor Relay" .
OK or NG
OK >> GO TO 5.
NG >> Replace rear blower motor relay.
5. CHECK REAR BLOWER MOTOR POWER FROM RELAY TO REAR BLOWER MOTOR
1. Reconnect rear blower motor connector.
2. Disconnect rear blower motor relay J-1.
3. Turn ignition switch ON.
4. Set rear blower switch (front) to any position except OFF, REAR, or 4 - speed.
5. Momentarily (no more than 4 seconds), connect a jumper wire between rear blower motor relay connector J-1 (harness side)
terminals 3 and 5.
OK or NG
OK >> GO TO 6.
NG >> GO TO 10. 2 - Ground
: Battery voltage.
WJIA0596E
Rear blower motor should rotate.WJIA0972E

ATC-106
TROUBLE DIAGNOSIS
Revision: November 20092006 QX56
6. CHECK REAR BLOWER MOTOR RELAY (COIL SIDE) POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect fuse block (J/B) connector M39.
3. Turn ignition switch ON.
4. Set rear blower switch (front) to any position except OFF, REAR, or 4 - speed.
5. Check voltage between fuse block (J/B) harness connector M39 terminal 3Q and ground.
OK or NG
OK >> GO TO 7.
NG >> GO TO 20.
7. CHECK REAR BLOWER MOTOR RELAY (COIL SIDE) GROUND CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect fuse block (J/B) connector M3.
3. Check continuity between fuse block (J/B) harness connector M3 terminal 7N and ground.
OK or NG
OK >> Replace fuse block (J/B).
NG >> Repair harness or connector.
8. REPLACE FUSE
Refer to PG-76, "
FUSE BLOCK-JUNCTION BOX (J/B)"
Fuse should not open when rear blower motor is activated.
OK or NG
OK >> Inspection End.
NG >> GO TO 9.
9. CHECK REAR BLOWER MOTOR POWER SUPPLY CIRCUIT FOR SHORT
1. Turn ignition switch OFF.
2. Disconnect fuse block (J/B) connector M3 and rear blower motor connector.
3. Check continuity between rear blower motor harness connector B134 terminal 2 and ground.
OK or NG
OK >> Check rear blower motor. Refer to ATC-100, "Front
Blower Motor" .
NG >> Repair harness or connector. 3Q - Ground : Battery voltage.
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7N - Ground
: Continuity should exist.
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2 - Ground: Continuity should not exist.
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Revision: November 2009 2006 QX56
10. CHECK REAR BLOWER MOTOR RELAY (SWITCH SIDE) POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect fuse block (J/B) and rear blower motor connectors.
3. Check continuity between fuse block (J/B) harness connector M3 terminal 3N and 8N and rear blower motor harness connec-
tor B134 terminal 2.
OK or NG
OK >> GO TO 20.
NG >> Repair harness or connector.
11 . CHECK REAR BLOWER MOTOR
Check rear blower motor. Refer to AT C - 111 , "
Rear Blower Motor" .
OK or NG
OK >> GO TO 12.
NG >> Replace rear blower motor. refer to ATC-150, "
REAR BLOWER MOTOR"
12. CHECK REAR BLOWER SWITCH (FRONT)
Refer to AT C - 11 0 , "
Rear Blower Switch (Front)" .
OK or NG
OK >> GO TO 15.
NG >> Replace rear blower switch (front). Refer to ATC-144, "
FRONT AIR CONTROL"
13. CHECK REAR BLOWER MOTOR RESISTOR
Refer to AT C - 111 , "
Rear Blower Motor Resistor" .
OK or NG
OK >> GO TO 14.
NG >> Replace rear blower motor resistor. Refer to ATC-165, "
REAR BLOWER MOTOR RESISTOR"
14. CHECK REAR BLOWER SWITCH (FRONT) CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect rear blower switch (front) M52.
3. Turn ignition switch ON.
4. Reconnect rear blower motor resistor harness connector B133.
5. Check voltage between each rear blower switch (front) connec- tor M52 terminals 3, 7, and 8, and ground.
OK or NG
OK >> GO TO 17.
NG >> GO TO 16. 3N, 8N - 2
: Continuity should exist.
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Terminal No.
Voltage
(+) (-)
3 Ground Approx. 12V
7
8
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ATC-108
TROUBLE DIAGNOSIS
Revision: November 20092006 QX56
15. CHECK REAR BLOWER MOTOR GROUND CIRCUIT TO REAR BLOWER MOTOR RESISTOR
1. Turn ignition switch OFF.
2. Disconnect rear blower motor and rear blower motor resistor connectors.
3. Check continuity between rear blower motor connector B134 (A) terminal 1 and rear blower motor resistor harness connector
B133 (B) terminal 3.
4. Check continuity between rear blower motor connector B134 (A) terminal 1 and ground.
OK or NG
OK >> GO TO 16.
NG >> Repair harness or connector.
16. CHECK REAR BLOWER SWITCH (FRONT) CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect rear blower motor resistor connector.
3. Check continuity between rear blower switch (front) connector M52 (A) terminals 3, 7, and 8, and rear blower motor resistor
connector B133 (B) terminals 1, 4, and 2.
OK or NG
OK >> Inspection End.
NG >> Repair harness or connector.
17. CHECK REAR BLOWER SWITCH (FRONT) CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect rear blower switch (rear) connectors.
3. Check continuity between rear blower switch (front) connector M52 terminals 3, 5, 7, and 8, and rear blower switch (rear) con-
nector R208 terminals 9, 6, 8, and 7.
OK or NG
OK >> GO TO 18.
NG >> Repair harness or connector. 1 - 3
: Continuity should exist.
1 - Ground : Continuity should not exist.
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Terminal No.
Continuity
Rear blower switch (front)
(A) Rear blower motor resistor
(B)
31 Ye s
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82
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Terminal No.
Continuity
Rear blower switch (front) Rear blower switch (rear)
39
Ye s
56
78
87
LJIA0110E

TROUBLE DIAGNOSISATC-109
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Revision: November 2009 2006 QX56
18. CHECK REAR BLOWER SWITCH (FRONT)
Refer to AT C - 11 0 , "
Rear Blower Switch (Front)" .
OK or NG
OK >> GO TO 19.
NG >> Replace rear blower switch (front). Refer to ATC-144, "
FRONT AIR CONTROL"
19. CHECK REAR BLOWER SWITCH (REAR)
Refer to AT C - 11 0 , "
Rear Blower Switch (Rear)" .
OK or NG
OK >> Inspection End.
NG >> Replace rear blower switch (rear). Refer to ATC-144, "
REAR AIR CONTROL"
20. CHECK CIRCUIT BETWEEN FRONT AIR CONTROL AND FUSE BLOCK (J/B) [REAR BLOWER
MOTOR RELAY (COIL SIDE) POWER]
1. Disconnect front air control and fuse block (J/B) connectors M39.
2. Check continuity between front air control harness connector M50 terminal 38 and fuse block (J/B) connector M39 terminal
3Q.
OK or NG
OK >> Replace front air control. Refer to ATC-144, "FRONT
AIR CONTROL" .
NG >> Repair harness or connector. Continuity should exist.LJIA0111E