relay INFINITI QX56 2007 Factory Owner's Manual

ATC-16
< SERVICE INFORMATION >
REFRIGERATION SYSTEM
REFRIGERATION SYSTEM
Refrigerant CycleINFOID:0000000003533229
REFRIGERANT FLOW
The refrigerant flows in the standard pattern, that is, through the compressor, the condenser with liquid tank,
through the front and rear evaporators, and back to the compressor. The refrigerant evaporation through the
evaporator coils are controlled by front and rear exter nally equalized expansion valves, located inside the front
and rear evaporator cases.
Refrigerant System ProtectionINFOID:0000000003533230
REFRIGERANT PRESSURE SENSOR
The refrigerant system is protected against excessively high or low pressures by the refrigerant pressure sen-
sor, located on the condenser. If the system pressure rise s above or falls below the specifications, the refriger-
ant pressure sensor detects the pressure inside t he refrigerant line and sends a voltage signal to the ECM.
The ECM de-energizes the A/C relay to disengage the magnetic compressor clutch when pressure on the high
pressure side detected by refrigerant pressu re sensor is over about 2,746 kPa (28 kg/cm
2, 398 psi), or below
about 120 kPa (1.22 kg/cm
2, 17.4 psi).
PRESSURE RELIEF VALVE
The refrigerant system is also protected by a pressure relief valve, located in the rear head of the compressor.
When the pressure of refrigerant in the system incr eases to an abnormal level [more than 2,990 kPa (30.5 kg/

AIR CONDITIONER CONTROLATC-23
< SERVICE INFORMATION >
C
DE
F
G H
I
K L
M A
B
AT C
N
O P
MAGNET CLUTCH CONTROL
When A/C switch or DEF switch is pressed, front air control inputs compressor ON signal to BCM.
BCM sends compressor ON signal to ECM and front air control via CAN communication line.
ECM judges whether compressor can be turned ON, based on each sensor status (refrigerant pressure sen-
sor signal, throttle angle sensor, etc.). If it judges compressor can be turned ON, it sends compressor ON sig-
nal to IPDM E/R, via CAN communication line.
Upon receipt of compressor ON signal from ECM, IPDM E/R turns air conditioner relay ON to operate com-
pressor.
SELF-DIAGNOSTIC SYSTEM
The self-diagnostic system is built into the front air cont rol to quickly locate the cause of symptoms. Refer to
ATC-48, "
A/C System Self-Diagnosis Function"
Description of Control SystemINFOID:0000000003533235
The control system consists of input sensors, swit ches, the front air control (microcomputer) and outputs.
WJIA2144E

TROUBLE DIAGNOSISATC-79
< SERVICE INFORMATION >
C
DE
F
G H
I
K L
M A
B
AT C
N
O P
1.CONFIRM SYMPTOM BY PERFORMING OPERATIONAL CHECK - FRONT BLOWER
1. Rotate the front blower control dial clockwise. Blower should operate.
2. Rotate the front blower control dial clockwise, and continue checking blower speed and fan symbol until
all speeds are checked.
Can the symptom be duplicated?
YES >> GO TO 3.
NO >> GO TO 2.
2.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.
3.CHECK FOR SERVICE BULLETINS
Check for any service bulletins.
>> GO TO 4.
4.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 5.
5.CHECK BLOWER MOTOR OPERATION
Check and verify blower motor operates manually in all speeds.
Does blower motor operate in all speeds?
YES >> GO TO 6.
NO >> Refer to "DIAGNOSTIC PROCEDURE FOR BLOWER MOTOR".
6.CHECK ENGINE COOLANT TEMPERATURE SENSOR CIRCUIT
Check engine coolant temperature sensor circuit. Refer to EC-205
.
OK or NG?
OK >> GO TO 7.
NG >> Refer to EC-207, "
Diagnosis Procedure".
7.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".
SYSTEM DESCRIPTION
Component Parts
Blower speed control system components are:• Front air control
• Variable blower control
• Front blower motor relay
• Front blower motor
• In-vehicle sensor
• Ambient sensor
• Optical sensor
• Intake sensor

ATC-82
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
1. Turn ignition switch OFF.
2. Disconnect front blower motor connector.
3. Turn ignition switch ON.
4. Press the mode switch to select any mode except OFF.
5. Turn the front blower control dial to high.
6. Check voltage between front blower motor harness connector M62 terminal 2 and ground.
OK or NG
OK >> GO TO 12.
NG >> GO TO 3.
3.CHECK FRONT BLOWER MOTOR RELAY (S WITCH SIDE) POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect front blower motor relay.
3. Check voltage between front blower motor relay harness con- nector M107 terminal 5 and ground.
OK or NG
OK >> GO TO 4.
NG >> Repair harness or connector.
4.CHECK FRONT BLOWER MOTOR RELAY
Turn ignition switch OFF.
Refer to "Front Blower Motor Relay" .
OK or NG
OK >> GO TO 5.
NG >> Replace front blower motor relay.
5.CHECK FRONT BLOWER MOTOR RELA Y (SWITCH SIDE) CIRCUIT FOR OPEN
Check continuity between front blower motor relay harness connec-
tor M107 terminal 3 and front blower motor harness connector M62
terminal 2.
OK or NG
OK >> GO TO 6.
NG >> Repair harness or connector.
6.CHECK VARIABLE BLOWER CONTROL POWER SUPPLY CIRCUIT FOR OPEN
1. Disconnect variable blower control harness connector.
2. Check continuity between front blower motor relay harness con- nector M107 terminals 3 and variable blower control harness
connector M122 terminal 1.
OK or NG
OK >> GO TO 7.
NG >> Repair harness or connector. 2 - Ground : Battery voltage.
WJIA1331E
5 - Ground : Battery voltage.
WJIA1886E
3 - 2 : Continuity should exist.
WJIA1360E
3 - 1 : Continuity should exist.
WJIA1361E

TROUBLE DIAGNOSISATC-83
< SERVICE INFORMATION >
C
DE
F
G H
I
K L
M A
B
AT C
N
O P
7.CHECK VARIABLE BLOWER CONTROL SIGNAL CIRCUIT
1. Disconnect front air control connector.
2. Check continuity between front air control harness connector
M49 terminal 13 and variable blower control harness connector
M122 terminal 2.
OK or NG
OK >> GO TO 8.
NG >> Repair harness or connector.
8.CHECK FRONT BLOWER MOTOR RELAY (COIL SIDE) POWER SUPPLY
1. Turn ignition switch ON.
2. Check voltage between front blower motor relay harness con- nector M107 terminal 2 and ground.
OK or NG
OK >> GO TO 9.
NG >> Repair harness or connector.
9.CHECK FRONT BLOWER MOTOR RELAY (COIL SIDE) GROUND CIRCUIT
1. Turn ignition switch OFF.
2. Check continuity between front blower motor relay connector M107 terminal 1 and front air control harness connector M49 ter-
minal 26.
OK or NG
OK >> Replace front air control. Refer to ATC-123, "Removal
and Installation" .
NG >> Repair harness or connector.
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 13 - 2 : Continuity should exist.
WJIA1362E
2 - Ground : Battery voltage.
WJIA1363E
1 - 26 : Continuity should exist.
WJIA1364E

ATC-84
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
1. Turn ignition switch OFF.
2. Disconnect front blower motor connector and variable blowercontrol connector.
3. Check continuity between variable blower control harness con-
nector M122 terminal 1 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.
2. Check continuity between front air control harness connector M49 terminal 13 and variable blower control harness connector
M122 terminal 2.
OK or NG
OK >> GO TO 13.
NG >> Repair harness or connector.
13.CHECK FRONT BLOWER MOTOR
Refer to "Front Blower Motor" .
OK or NG
OK >> GO TO 14.
NG >> Replace front blower motor. Refer to ATC-123, "
Removal and Installation"
14.CHECK BLOWER MOTOR GROUND CIRCUIT
Check continuity between front blower motor harness connector
M62 terminal 1 and variable blower control harness connector M122
terminal 3.
OK or NG
OK >> GO TO 15.
NG >> Repair harness or connector.
15.CHECK VARIABLE BLOWER CONTROL GROUND CIRCUIT
Check continuity between variable blower control harness connector
M122 terminal 4 and ground.
OK or NG
OK >> Replace variable blower control. Refer to ATC-143.
NG >> Repair harness or connector.
COMPONENT INSPECTION
Front Blower Motor Relay
1 - Ground. : Continuity should not exist.
WJIA1365E
13 - 2 : Continuity should exist.
WJIA1366E
1 - 3 : Continuity should exist.
WJIA1367E
4 - ground : Continuity should exist.
WJIA1368E

TROUBLE DIAGNOSISATC-85
< SERVICE INFORMATION >
C
DE
F
G H
I
K L
M A
B
AT C
N
O P
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.
Rear Blower Motor CircuitINFOID:0000000003533257
SYMPTOM:
• Blower motor operation is malfunctioning.
INSPECTION FLOW
1.CONFIRM SYMPTOM BY PERFORMING OPERATIO NAL CHECK - REAR AIR CONTROL (FRONT)
1. Press AUTO switch.
2. Set the rear blower control dial (front) to REAR position.
3. Turn the rear blower control dial (rear) and check for rear blower operation. NOTE:
If the engine coolant temperature increases above 111.9 °C (233.6 °F) the front air control turns OFF the
rear blower motor. When the engine coolant temperature drops below 110 °C (230 °F) the front air control
turns the rear blower motor back ON.
4. Continue checking that rear blower speed increases as the rear blower control dial is rotated clockwise.
Does the rear blower motor operate correctly?
YES >> GO TO 3.
NO >> GO TO 2.
2.CHECK FOR ANY SYMPTOMS
WJIA1401E
WJIA1508E

ATC-86
< 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 CONTROL DIAL (FRONT) CIRCUIT
Check and verify rear blower control dial (front ) operates the rear blower motor in all speeds.
Does blower motor operate in all speeds?
YES >> GO TO 5.
NO >> Refer to ATC-93, "
Rear Air Control Circuit".
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" .
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
WJIA1280E

TROUBLE DIAGNOSISATC-89
< SERVICE INFORMATION >
C
DE
F
G H
I
K L
M A
B
AT C
N
O P
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.
WJIA0972E
3Q - Ground : Battery voltage.
LJIA0101E
7N - Ground : Continuity should exist.
WJIA0597E

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.
WJIA0598E
3N, 8N - 2 : Continuity should exist.
WJIA0599E
Te r m i n a l N o .
Voltage
(+) (-)
3 Ground Approx. 12V
7
8
LJIA0108E