2007 INFINITI QX56 service

ATC-88
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
Perform a complete operational check for any symptoms. Refer to ATC-50, "Operational Check (Front)".
Does another symptom exist?
YES >> Refer to ATC-32, "How to Perform Trouble Diagnosis for Quick and Accurate Repair" .
NO >> System OK.
3.CHECK FOR SERVICE BULLETINS
Check for any service bulletins.
>> GO TO 4.
4.CHECK REAR BLOWER MOTOR CIRCUIT
Check and verify rear blower motor operates in all speeds.
Does blower motor operate in all speeds?
YES >> GO TO 5.
NO >> Refer to "Trouble Diagnosis Procedure For Rear Blower Motor (1 - 4 Speed)".
5.PERFORM SELF-DIAGNOSIS
Perform self-diagnosis to check for any codes. Refer to ATC-48, "
A/C System Self-Diagnosis Function" .
Are any self-diagnosis codes present?
YES >> Refer to ATC-48, "A/C System Self-Diagnosis Function".
NO >> GO TO 6.
6.RECHECK FOR ANY SYMPTOMS
Perform a complete operational check for any symptoms. Refer to ATC-50, "
Operational Check (Front)" .
Does another symptom exist?
YES >> Refer to ATC-32, "How to Perform Trouble Diagnosis for Quick and Accurate Repair".
NO >> Replace front air control. Refer to ATC-123, "
Removal and Installation".
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-73
.
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. 2 - Ground : Battery voltage.WJIA0596E

TROUBLE DIAGNOSISATC-89
< SERVICE INFORMATION >
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4.CHECK REAR BLOWER MOTOR RELAY
Turn ignition switch OFF.
Refer to "Rear Blower Motor Relay".
OK or NG
OK >> GO TO 5.
NG >> Replace rear blower motor relay.
5.CHECK REAR BLOWER MOTOR POWER FR OM 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.
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 RE LAY (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-73
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 SHORTRear blower motor should rotate.
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3Q - Ground : Battery voltage.
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7N - Ground : Continuity should exist.
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ATC-90
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
1. Turn ignition switch OFF.
2. Disconnect fuse block (J/B) connector M3 and rear blower motorconnector.
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-78, "Front
Blower Motor Circuit".
NG >> Repair harness or connector.
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 fu se 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 "Rear Blower Motor".
OK or NG
OK >> GO TO 12.
NG >> Replace rear blower motor. refer to ATC-128, "
Removal and Installation"
12.CHECK REAR BLOWER SWITCH (FRONT)
Refer to "Rear Blower Switch (Front)" .
OK or NG
OK >> GO TO 15.
NG >> Replace rear blower switch (front). Refer to ATC-123, "
Removal and Installation"
13.CHECK REAR BLOWER MOTOR RESISTOR
Refer to "Rear Blower Motor Resistor".
OK or NG
OK >> GO TO 14.
NG >> Replace rear blower motor resistor. Refer to ATC-144
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.2 - Ground : Continuity should not exist.
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3N, 8N - 2 : Continuity should exist.
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Te r m i n a l N o .
Voltage
(+) (-)
3 Ground Approx. 12V
7
8
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TROUBLE DIAGNOSISATC-91
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OK or NG
OK >> GO TO 17.
NG >> GO TO 16.
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 (B) 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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Te r m i n a l N o .
Continuity
Rear blower switch (front) (A) R ear blower motor resistor (B)
31 Ye s
74
82
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Te r m i n a l N o .
Continuity
Rear blower switch (front) Rear blower switch (rear)
39
Ye s
56
78
87
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ATC-92
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
18.CHECK REAR BLOWER SWITCH (FRONT)
Refer to "Rear Blower Switch (Front)".
OK or NG
OK >> GO TO 19.
NG >> Replace rear blower switch (front). Refer to ATC-123, "
Removal and Installation"
19.CHECK REAR BLOWER SWITCH (REAR)
Refer to "Rear Blower Switch (Rear)" .
OK or NG
OK >> Inspection End.
NG >> Replace rear blower switch (rear). Refer to ATC-123, "
Removal and Installation"
20.CHECK CIRCUIT BETWEEN FRONT AIR CONTROL AND FUSE BLOCK (J/B) [REAR BLOWER MO-
TOR 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-123, "Removal
and Installation" .
NG >> Repair harness or connector.
COMPONENT INSPECTION
Rear Blower Motor Relay
Check circuit continuity between terminals by supplying 12 volts and
ground to coil side terminals of relays.
Rear Blower Switch (Rear)
Continuity should exist.
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TROUBLE DIAGNOSISATC-93
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Check continuity between terminals at each switch position.
Rear Blower Switch (Front)
Check continuity between terminals at each switch position.
Rear Blower Motor
Check that there are no foreign particles inside the intake unit.
Apply 12 volts to terminal 2 and ground to terminal 1 and ensure that
the blower motor rotates freely and quietly.
Rear Blower Motor Resistor
Check continuity between terminals. There will be resistance, but
there should not be an open or short between any two terminals.
Rear Air Control CircuitINFOID:0000000003533258
SYMPTOM:
• Temperature cannot be adjusted from the rear air control.
INSPECTION FLOW
1.CONFIRM SYMPTOM BY PERFORMING OPERAT IONAL CHECK - TEMPERATURE INCREASE
1. Press AUTO switch.
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ATC-94
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
2. Turn the rear blower motor on (1-4 speed).
3. Turn the rear temperature/mode control dial clockwise.
4. Check for hot air at rear foot discharge air outlets.>> GO TO 2.
2.CONFIRM SYMPTOM BY PERFORMING OPER ATIONAL CHECK - TEMPERATURE DECREASE
1. Turn the rear temperature/mode control dial counterclockwise.
2. Check for cold air at rear vent discharge air outlets.
OK or NG?
YES >> GO TO 3.
NO >> GO TO 4.
3.CHECK FOR ANY SYMPTOMS
Perform a complete operational check for any symptoms. Refer to ATC-50, "
Operational Check (Front)" .
Does another symptom exist?
YES >> Refer to ATC-32, "How to Perform Trouble Diagnosis for Quick and Accurate Repair" .
NO >> System OK.
4.CHECK FOR SERVICE BULLETINS
Check for any service bulletins.
>> GO TO 5.
5.PERFORM SELF-DIAGNOSIS
Perform self-diagnosis to check for any codes. Refer to ATC-48, "
A/C System Self-Diagnosis Function" .
Are any self-diagnosis codes present?
YES >> Refer to ATC-48, "A/C System Self-Diagnosis Function".
NO >> GO TO 6.
6.CHECK REAR TEMPERATURE/MODE CONTROL DIAL OPERATION
Check and verify rear outlet position and temperat ure change when adjusted from front air control.
OK or NG?
YES >> Check rear air control circuit. Refer to "DIAGNOSTIC PROCEDURE FOR REAR AIR CONTROL".
NO >> Check air mix door motor (rear). Refer to ATC-59, "
Air Mix Door Motor Circuit" .
SYSTEM DESCRIPTION
Component Parts
Rear air control system components are:
• Front air control
• Rear air control
• Air mix door motor (rear)
• Rear blower motor relay
• Rear blower motor resistor
• Rear blower motor

TROUBLE DIAGNOSISATC-95
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System Operation
Rear Air Control
When the rear blower switch (front) (integral to the front
air control) is in the REAR position the rear blower
motor speeds and the rear temperature and mode are contro lled by the rear blower switch (rear) and the rear
temperature switch (rear) (both integral to the rear air control).
DIAGNOSTIC PROCEDURE FOR REAR AIR CONTROL
SYMPTOM:
• Blower motor operation is malfunctioning. Refer to ATC-85, "Rear Blower Motor Circuit" .
• Temperature and mode operation is malfunctioning.
1.CHECK OPERATION FROM FRONT AIR CONTROL
Does rear temperature and mode operat e normally from front air control?
YES or NO
YES >> GO TO 2.
NO >> Refer to ATC-59, "
Air Mix Door Motor Circuit".
2.CHECK CIRCUIT BETWEEN REAR AIR CONTROL AND FRONT AIR CONTROL FOR OPEN AND
SHORT
1. Turn ignition switch OFF.
2. Disconnect front air control and rear air control connectors.
3. Check continuity between front air control harness connector
M50 terminal 33 and rear air control harness connector R209
terminal 5.
4. Check continuity between rear air control harness connector R209 terminal 5 and ground.
OK or NG
OK >> GO TO 3.
NG >> Repair harness or connector.
3.CHECK CIRCUIT BETWEEN REAR AI R CONTROL AND AIR MIX DOOR MOTOR (REAR) FOR OPEN OR
SHORT
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33 - 5 Continuity should exist.
5 - Ground Continuity should not exist.
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