2004 INFINITI QX56 sensor

ATC-132
TROUBLE DIAGNOSIS
Revision: August 20072004 QX56
DIAGNOSTIC PROCEDURE FOR OPTICAL SENSOR
SYMPTOM: Optical sensor circuit is open or shorted. [50 (Driver) or
52 (Passenger) is indicated as a result of conducting self-diagnosis.]
1. CHECK CIRCUIT CONTINUITY BETWEEN OPTICAL SENSOR AND FRONT AIR CONTROL
1. Turn ignition switch OFF.
2. Disconnect front air control connector M50 and optical sensor
connector M402.
3. Check continuity between optical sensor harness connector
M402 terminal 1 (W/V) and 2 (G/O) and front air control harness
connector M50 terminal 31 (W/V) and 40 (G/O).
4. Check continuity between optical sensor harness connector
M402 terminal 1 (W/V) and 2 (G/O) and ground.
OK or NG
OK >> GO TO 2.
NG >> Repair harness or connector.
2. CHECK CIRCUIT CONTINUITY BETWEEN OPTICAL SENSOR AND BCM
1. Disconnect BCM connector M18.
2. Check continuity between optical sensor harness connector
M402 terminal 3 (P) and BCM harness connector M18 terminal
18 (P).
3. Check continuity between optical sensor harness connector
M402 terminal 3 (P) and ground.
OK or NG
OK >> Replace optical sensor. Refer to ATC-138, "OPTICAL SENSOR" .
NG >> Repair harness or connector.
WJIA0826E
1 - 31 : Continuity should exist.
2 - 40 : Continuity should exist.
1, 2 - Ground. : Continuity should not exist.
WJIA0827E
3 - 18 : Continuity should exist.
3 - Ground : Continuity should not exist.
WJIA0828E

TROUBLE DIAGNOSIS
ATC-133
C
D
E
F
G
H
I
K
L
MA
B
AT C
Revision: August 20072004 QX56
Intake Sensor CircuitEJS002CV
COMPONENT DESCRIPTION
Intake Sensor
The intake sensor is located on the front heater & cooling unit. It con-
verts temperature of air after it passes through the evaporator into a
resistance value which is then input to the front air control.
DIAGNOSTIC PROCEDURE FOR INTAKE SENSOR
SYMPTOM: Intake sensor circuit is open or shorted. (56 or 57 is indi-
cated as a result of conducting self-diagnosis).
1. CHECK VOLTAGE BETWEEN INTAKE SENSOR AND GROUND
1. Disconnect intake sensor connector M146.
2. Turn ignition switch ON.
3. Check voltage between intake sensor harness connector M146
terminal 2 (L/B) and ground.
OK or NG
OK >> GO TO 2.
NG >> GO TO 4.
2. CHECK CIRCUIT CONTINUITY BETWEEN INTAKE SENSOR AND FRONT AIR CONTROL
1. Turn ignition switch OFF.
2. Disconnect front air control connector M49.
3. Check continuity between intake sensor harness connector
M146 terminal 1 (V/R) and front air control harness connector
M49 terminal 21 (V/R).
OK or NG
OK >> GO TO 3.
NG >> Repair harness or connector.
WJIA0571E
WJIA0464E
2 - Ground : Approx. 5V
WJIA0829E
1 - 21 : Continuity should exist.
WJIA0830E

ATC-134
TROUBLE DIAGNOSIS
Revision: August 20072004 QX56
3. CHECK INTAKE SENSOR
Refer to ATC-134, "
Intake Sensor" .
OK or NG
OK >> 1. Replace front air control. Refer to ATC-135, "FRONT AIR CONTROL" .
2. Go to self-diagnosis ATC-53, "
A/C System Self-diagnosis Function" and perform self-diagno-
sis.
NG >> 1. Replace intake sensor. Refer to ATC-139, "
INTAKE SENSOR" .
2. Go to self-diagnosis ATC-53, "
A/C System Self-diagnosis Function" and perform self-diagno-
sis.
4. CHECK CIRCUIT CONTINUITY BETWEEN INTAKE SENSOR AND FRONT AIR CONTROL
1. Turn ignition switch OFF.
2. Disconnect front air control connector M49.
3. Check continuity between intake sensor harness connector
M146 terminal 2 (L/B) and front air control harness connector
M49 terminal 9 (L/B).
4. Check continuity between intake sensor harness connector
M146 terminal 2 (L/B) and ground.
OK or NG
OK >> 1. Replace front air control. Refer to ATC-135, "FRONT AIR CONTROL" .
2. Go to self-diagnosis ATC-53, "
A/C System Self-diagnosis Function" and perform self-diagno-
sis.
NG >> Repair harness or connector.
COMPONENT INSPECTION
Intake Sensor
After disconnecting intake sensor connector, measure resistance
between terminals 1 and 2 at sensor harness side, using the table
below.
If NG, replace intake sensor.2 - 9 : Continuity should exist.
2 - Ground : Continuity should not exist.
WJIA0831E
Temperature °C (°F) Resistance kΩ
−15 (5) 209.0
−10 (14) 160.0
−5 (23) 123.0
0 (32) 95.8
5 (41) 74.9
10 (50) 58.9
15 (59) 46.7
20 (68) 37.3
25 (77) 30.0
30 (86) 24.2
35 (95) 19.7
40 (104) 16.1
45 (113) 13.2
WJIA0832E

ATC-136
AMBIENT SENSOR
Revision: August 20072004 QX56
AMBIENT SENSORPFP:27722
Removal and InstallationEJS002CX
REMOVAL
1. Disconnect the ambient sensor electrical connector.
NOTE:
The ambient sensor is located behind the front bumper, in front
of the condenser.
2. Release the ambient sensor clip and then remove the ambient
sensor.
INSTALLATION
Installation is in the reverse order of removal.
WJIA0819E

IN-VEHICLE SENSOR
ATC-137
C
D
E
F
G
H
I
K
L
MA
B
AT C
Revision: August 20072004 QX56
IN-VEHICLE SENSORPFP:27720
Removal and InstallationEJS002CY
REMOVAL
1. Remove the cluster lid D. Refer to IP-12, "Cluster Lid D" .
2. Remove the two screws and remove the in-vehicle sensor.
INSTALLATION
Installation is in the reverse order of removal.
LJIA0132E

ATC-138
OPTICAL SENSOR
Revision: August 20072004 QX56
OPTICAL SENSORPFP:28576
Removal and InstallationEJS002CZ
The optical sensor is located in the top center of the instrument
panel. Refer to LT- 6 4 , "
Removal and Installation of Optical Sensor" .
WJIA0607E

INTAKE SENSOR
ATC-139
C
D
E
F
G
H
I
K
L
MA
B
AT C
Revision: August 20072004 QX56
INTAKE SENSORPFP:27723
Removal and InstallationEJS002D0
REMOVAL
1. Remove the instrument panel. Refer to IP-10, "INSTRUMENT PANEL ASSEMBLY" .
2. Disconnect the intake sensor electrical connector.
NOTE:
The intake sensor is located on the top of the front heater and
cooling unit assembly next to the A/C evaporator cover.
3. Twist the intake sensor to remove the intake sensor from the
front heater and cooling unit assembly.
INSTALLATION
Installation is in the reverse order of removal.
LJIA0133E

REFRIGERANT LINES
ATC-165
C
D
E
F
G
H
I
K
L
MA
B
AT C
Revision: August 20072004 QX56
Rear A/C
NOTE:
Refer to AT C - 7 , "
Precautions for Refrigerant Connection" .
1. High-pressure service valve 2. Grommet 3. High-pressure pipe
4. Refrigerant pressure sensor 5. Condenser 6. Compressor shaft seal
7. High-pressure flexible hose 8. Low-pressure flexible hose 9. Low-pressure service valve
10. Low-pressure pipe 11. Expansion valve (front) 12. Drain hose
WJIA2315E
1. Rear heater and cooling unit assembly 2. Rear A/C pipes 3. Rear A/C heater core pipes
4. Rear heater core hose 5. Rear blower motor 6. Underfloor rear A/C pipes
7. Underfloor rear heater core pipes A. Bolt torque specifications B. Leak checking order (l - r)
C. Tightening torque D. Wrench size E. O-ring size
⇐Front
NOTE: The O-ring size 8 is the high-side and the O-ring size 16 is the low-side.