2005 INFINITI QX4 air condition

TROUBLE DIAGNOSIS FOR SELF-DIAGNOSTIC ITEMS
BRC-41
[VDC/TCS/ABS]
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BRC
Revision: October 20052005 QX56
Steering Angle Sensor SystemEFS004XU
INSPECTION PROCEDURE
1. CHECK SELF-DIAGNOSIS RESULT
Check self-diagnosis results.
Is above displayed in self-diagnosis item?
YES >> GO TO 2.
NO >> Inspection End.
2. CHECK CONNECTOR
1. Disconnect steering angle sensor connector M47 and ABS actuator and electric unit (control unit) connec-
tor E125 and check terminals for deformation, disconnection, looseness, or damage. Repair or replace as
necessary.
2. Reconnect connectors and repeat ABS actuator and electric unit (control unit) self-diagnosis.
IS "ST ANGLE SEN CIRCUIT" or "ST ANG SEN COM CIR" DISPLAYED?
YES >> GO TO 3.
NO >> Inspection End.
3. CHECK STEERING ANGLE SENSOR HARNESS
1. Check CAN communication system. Refer to LAN-5, "
CAN COMMUNICATION" .
2. Turn ignition switch OFF and disconnect steering angle sensor
connector M47 and ABS actuator and electric unit (control unit)
connector E125.
3. Check continuity between ABS actuator and electric unit (control
unit) connector E125 and steering angle sensor connector M47.
OK or NG
OK >> GO TO 4.
NG >> Repair or replace harness.
4. CHECK DATA MONITOR
1. Connect steering angle sensor and ABS actuator and electric unit (control unit) connectors.
2. Use “DATA MONITOR” to check if the status of "STR ANGLE SIG" is normal.
OK or NG
OK >> Perform ABS actuator and electric unit (control unit) self-diagnosis again.
NG >> Replace spiral cable (steering angle sensor) and adjust neutral position of steering angle sensor.
Refer to BRC-62, "
Adjustment of Steering Angle Sensor Neutral Position" .
Self-diagnosis results
ST ANGLE SEN CIRCUIT
ST ANG SEN COM CIR
ABS actuator and
electric unit (con-
trol unit) harness
connector E125Steering angle
sensor
harness con-
nector M47Continuity
11 (L) 3 (L) Yes
15 (P) 4 (P) Yes
WFIA0224E
Steering condition Data monitor
Straight-ahead –3.5 deg to +3.5 deg
Turn wheel to the right by 90°Approx. - 90deg
Turn wheel to the left by 90°Approx. + 90deg

BRC-50
[VDC/TCS/ABS]
TROUBLE DIAGNOSIS FOR SELF-DIAGNOSTIC ITEMS
Revision: October 20052005 QX56
4. ACTIVE BOOSTER SENSOR INSPECTION
1. Reconnect the active booster and ABS actuator and electric unit (control unit) connectors.
2. Use "DATA MONITOR" to check if the status of "RELEASE SW NO" and "RELEASE SW NC" is normal.
OK or NG
OK >> Inspection End.
NG >> Replace active booster.
Delta Stroke Sensor System InspectionEFS004Y2
INSPECTION PROCEDURE
1. DISPLAY SELF DIAGNOSIS RESULTS
Check self-diagnosis result display item.
Is the above displayed in the self-diagnosis display items?
YES or NO
YES >> GO TO 2.
NO >> Inspection End.
2. CONNECTOR INSPECTION
1. Turn the ignition switch OFF.
2. Disconnect the delta stroke sensor connector E114 and ABS actuator and electric unit (control unit) con-
nector E125 and inspect the terminals for deformation, disconnection, looseness, or damage.
OK or NG
OK >> GO TO 3.
NG >> Repair connector.ConditionData monitor display
RELEASE SW NO RELEASE SW NC
When brake pedal is depressed ON OFF
When brake pedal is released OFF ON
Self-diagnosis results
DELTA S SEN NG

TROUBLE DIAGNOSIS FOR SELF-DIAGNOSTIC ITEMS
BRC-51
[VDC/TCS/ABS]
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BRC
Revision: October 20052005 QX56
3. DELTA STROKE SENSOR CIRCUIT INSPECTION
1. Measure the continuity between the ABS actuator and electric unit (control unit) connector E125 and delta
stroke sensor connector E114.
2. Measure the continuity between the ABS actuator and electric unit (control unit) connector E125 and body
ground.
OK or NG
OK >> GO TO 4.
NG >> Repair or replace harness or connector.
4. DELTA STROKE SENSOR INSPECTION
1. Reconnect the delta stroke sensor and ABS actuator and electric unit (control unit) connectors.
2. Use "DATA MONITOR" to check if the status of "DELTA S SEN" is normal.
OK or NG
OK >> Inspection End.
NG >> Replace delta stroke sensor.
Pressure Sensor System InspectionEFS004Y3
FRONT PRESSURE INSPECTION PROCEDURE
1. DISPLAY SELF DIAGNOSIS RESULTS
Check self-diagnosis result display item.
Is the above displayed in the self-diagnosis display items?
YES or NO
YES >> GO TO 2.
NO >> Inspection End.ABS actuator and electric unit
(control unit) connector E125Delta stroke sensor
connector E114Continuity
26 (W/V) 1 (W/V)
Yes 39 (G/B) 3 (G/B)
40 (R/Y) 5 (R/Y)
ABS actuator and electric unit
(control unit) connector E125Body ground Continuity
26 (W/V)
—No 39 (G/B)
40 (R/Y)
ConditionData monitor display (Approx.)
DELTA S SEN
When brake pedal is released 0.00 mm (+0.6/-0.4)
When brake pedal is depressed 1.05–1.80 mm
Self-diagnosis results
PRESS SENSE CIRCUIT

BRC-52
[VDC/TCS/ABS]
TROUBLE DIAGNOSIS FOR SELF-DIAGNOSTIC ITEMS
Revision: October 20052005 QX56
2. CONNECTOR INSPECTION
1. Turn the ignition switch OFF.
2. Disconnect the front pressure sensor connector E31 and ABS actuator and electric unit (control unit) con-
nector E125 and inspect the terminals for deformation, disconnection, looseness, or damage.
OK or NG
OK >> GO TO 3.
NG >> Repair connector.
3. FRONT PRESSURE SENSOR CIRCUIT INSPECTION
1. Measure the continuity between the ABS actuator and electric unit (control unit) harness connector E125
and front pressure sensor harness connector E31.
2. Measure the continuity between the ABS actuator and electric unit (control unit) harness connector E125
and body ground.
OK or NG
OK >> GO TO 4.
NG >> Repair or replace harness or connector.
4. FRONT PRESSURE SENSOR INSPECTION
1. Reconnect the front pressure sensor and ABS actuator and electric unit (control unit) connectors.
2. Use "DATA MONITOR" to check if the status of "PRESS SENSOR" is normal.
OK or NG
OK >> Inspection End.
NG >> Replace pressure sensor.ABS actuator and electric unit
(control unit) harness connector
E125Front pressure sensor har-
ness connector E31 Continuity
18 (LG) 3 (LG)
Ye s 19 (SB) 1 (SB)
20 (R/L) 2 (R/L)
ABS actuator and electric unit
(control unit) harness connector
E125Body ground Continuity
18 (LG)
—No 19 (SB)
20 (R/L)
ConditionData monitor display (Approx.)
PRESS SENSOR
When brake pedal is depressed Positive value
When brake pedal is released 0 bar

BRC-54
[VDC/TCS/ABS]
TROUBLE DIAGNOSIS FOR SELF-DIAGNOSTIC ITEMS
Revision: October 20052005 QX56
4. REAR PRESSURE SENSOR INSPECTION
1. Reconnect the rear pressure sensor and ABS actuator and electric unit (control unit) connectors.
2. Use "DATA MONITOR" to check if the status of "PRESS SEN 2" is normal.
OK or NG
OK >> Inspection End.
NG >> Replace rear pressure sensor.
Steering Angle Sensor Safe Mode InspectionEFS00695
INSPECTION PROCEDURE
1. INDICATOR LAMP CHECK
Check that VDC OFF indicator lamp is on.
OK or NG
OK >> GO TO 2.
NG >> GO TO 3.
2. ADJUSTMENT OF STEERING ANGLE SENSOR NEUTRAL POSITION
Adjust steering angle sensor neutral position. Refer to BRC-62, "
Adjustment of Steering Angle Sensor Neutral
Position" .
OK or NG
OK >> GO TO 3.
NG >> Check steering angle sensor. Refer to BRC-41, "
Steering Angle Sensor System" .
3. INDICATOR LAMP CHECK
Check that VDC OFF indicator lamp is off.
OK or NG
OK >> GO TO 4.
NG >> Perform basic inspection. Refer to BRC-23, "
Basic Inspection" .
4. CHECK SELF-DIAGNOSTIC RESULTS
Perform ABS actuator and electric unit (control unit) self-diagnosis.
NOTE:
When self-diagnostic results show items other than those above, perform repair or replacement for the item
indicated and repeat self-diagnosis.
Is the above displayed on self-diagnosis display?
YES >> Erase error memory.
NO >> Inspection End.ConditionData monitor display (Approx.)
PRESS SEN 2
When brake pedal is depressed Positive value
When brake pedal is released 0 bar
Self-diagnosis results
ST ANGL SEN SAFE

BRC-58
[VDC/TCS/ABS]
TROUBLE DIAGNOSES FOR SYMPTOMS
Revision: October 20052005 QX56
Unexpected Pedal ActionEF S0 04 YA
1. CHECK WARNING LAMP ACTIVATION
Make sure warning lamp remains off while driving.
OK or NG
OK >> GO TO 2.
NG >> Carry out self-diagnosis. Refer to BRC-29, "
SELF-DIAGNOSIS" .
2. CHECK BRAKE PEDAL STROKE
Check brake pedal stroke.
Is pedal stroke excessive?
YES >> Perform Basic Inspection. Refer to BRC-23, "Basic
Inspection" .
NO >> GO TO 3.
3. CHECK CONNECTOR AND BRAKING PERFORMANCE
1. Disable ABS by disconnecting ABS actuator and electric unit (control unit) connector.
2. Drive vehicle and check brake operation.
NOTE:

Stopping distance may be longer than vehicles without ABS when road condition is slippery.

Driving the vehicle with the ABS actuator and electric unit (control unit) disconnected may induce DTCs
in electrical control units using CAN communication. After the inspection, clear all DTCs. Refer to BRC-
10, "CAN COMMUNICATION" .
OK or NG
OK >> GO TO 4.
NG >> Perform Basic Inspection. Refer to BRC-23, "
Basic Inspection" .
4. CHECK WHEEL SENSORS
Check the following.

Wheel sensor mounting for looseness

Wheel sensors for physical damage

Wheel sensor connectors for terminal damage or loose connections
OK or NG
OK >> Check ABS actuator and electric unit (control unit) connector terminals for deformation, discon-
nection, looseness or damage. Reconnect ABS actuator and electric unit (control unit) harness
connector. Then retest.
NG >> Repair or replace as necessary.
SBR5 40 A

CO-14Revision: October 2005
RADIATOR
2005 QX56
10. Lift up and remove the radiator.
CAUTION:
Do not damage or scratch air conditioner condenser and
radiator core when removing.
INSTALLATION
Installation is in the reverse order of removal.
INSPECTION AFTER INSTALLATION

Check for leaks of engine coolant. Refer to CO-10, "CHECKING COOLING SYSTEM FOR LEAKS" .

Start and warm up the engine. Visually check for leaks of the engine coolant and A/T fluid.
Checking RadiatorEBS00LN9
Check radiator for mud or clogging. If necessary, clean radiator as follows.
CAUTION:

Be careful not to bend or damage the radiator fins.

When radiator is cleaned without removal, remove all surrounding parts such as cooling fan, radi-
ator shroud and horns. Then tape the harness and electrical connectors to prevent water from
entering.
1. Apply water by hose to the back side of the radiator core vertically downward.
2. Apply water again to all radiator core surfaces.
3. Stop washing when dirt and debris no longer flow out from the radiator.
4. Blow air into the back side of radiator core vertically downward.

Use compressed air lower than 490 kPa (5 kg/cm2 , 71 psi) and keep distance more than 30 cm (11.8
in).
5. Blow air again into all the radiator core surfaces until no water sprays out.
PBIC1536E

ENGINE COOLING FAN
CO-15
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Revision: October 20052005 QX56
ENGINE COOLING FANPFP:21140
Removal and Installation (Crankshaft Driven Type)EBS00LNA
REMOVAL
1. Remove the air duct and resonator assembly. Refer to EM-14, "Removal and Installation" .
2. Remove the engine front undercover using power tool.
3. Remove the lower radiator shroud. Refer to CO-12, "
Removal and Installation" .
4. Remove the drive belt. Refer to EM-12, "
Removal and Installation" .
5. Remove the cooling fan.
INSPECTION AFTER REMOVAL
Fan Coupling
Inspect fan coupling for oil leakage and bimetal conditions.
Fan Bracket

Visually check that there is no significant looseness in the fan
bracket shaft, and that it turns smoothly by hand.

If there are any unusual concerns, replace the cooling fan pulley.
INSTALLATION
Installation is in the reverse order of removal.

Install cooling fan with its front mark “F” facing front of engine. Refer to CO-15, "Removal and Installation
(Crankshaft Driven Type)" .
INSPECTION AFTER INSTALLATION

Check for leaks of the engine coolant. Refer to CO-10, "CHECKING COOLING SYSTEM FOR LEAKS" .
1. Cooling fan 2. Fan coupling 3. Fan bracket
4. Cooling fan pulley
WBIA0632E
SL C0 72
WBIA0418E