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![INFINITI QX56 2004 Factory Service Manual TROUBLE DIAGNOSIS FOR SELF-DIAGNOSTIC ITEMS
ACS-41
[ICC]
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6. CHECK ICC BRAKE HOLD RELAY
1. Turn ignition switch OFF.
2. Remove ICC brake hold r INFINITI QX56 2004 Factory Service Manual TROUBLE DIAGNOSIS FOR SELF-DIAGNOSTIC ITEMS
ACS-41
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6. CHECK ICC BRAKE HOLD RELAY
1. Turn ignition switch OFF.
2. Remove ICC brake hold r](/manual-img/42/57034/w960_57034-49.png)
TROUBLE DIAGNOSIS FOR SELF-DIAGNOSTIC ITEMS
ACS-41
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6. CHECK ICC BRAKE HOLD RELAY
1. Turn ignition switch OFF.
2. Remove ICC brake hold relay.
3. Check continuity between terminals of ICC brake hold relay.
OK or NG
OK >> GO TO 7.
NG >> Replace ICC brake hold relay. Erase DTC and perform
ICC system running test. Then perform self-diagnosis of
ICC system again.
7. CHECK ICC BRAKE HOLD RELAY CIRCUIT
1. Disconnect connectors of ICC unit and stop lamp switch.
2. Check continuity between ICC unit harness connector B17 ter-
minal 38 (R/G) and ICC brake hold relay harness connector
E134 terminal 7 (R/G).
3. Check continuity between ICC unit harness connector B17 ter-
minal 38 (R/G) and stop lamp switch harness connector E38 ter-
minal 4 (R/G).
OK or NG
OK >> Replace ICC unit. Refer to ACS-59, "ICC Unit" . Erase
DTC and perform ICC system running test. Then perform self-diagnosis of ICC system again.
NG >>
Repair harness between ICC unit and ICC brake hold relay or stop lamp switch.
After repair, erase DTC and perform ICC system running test. Then, perform self-diagnosis of
ICC system again.
DTC 46 OPERATION SW CIRCEKS007X9
1. CHECK ECM CONNECTOR
1. Turn ignition switch OFF.
2. Disconnect ECM connector, and connect it securely again. Then erase DTC. Then, perform self-diagnosis
of ICC system again.
OK or NG
OK >>Poor connector connection.
Check connector. (Check connector housing for disconnected, loose, bent, and collapsed ter-
minals. If any malfunction is detected, repair applicable part.) After repair, erase DTC, and per-
form ICC system running test. Then perform self-diagnosis of ICC system again.
NG >> GO TO 2.
2. CHECK ICC STEERING SWITCH
Check ICC steering switch. Refer to ACS-58, "ICC Steering Switch" .
OK or NG
OK >> GO TO 3.
NG >> Replace ICC steering switch assembly. Refer to ACS-59, "
ICC Steering Switch" . Erase DTC and
perform ICC system running test. Then perform self-diagnosis of ICC system again. 7 - 6 Continuity should not exist.
4 - 3 Continuity should exist.
SKIA6651E
Continuity should exist.
Continuity should exist.
WKIA3403E
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![INFINITI QX56 2004 Factory Service Manual ACS-42
[ICC]
TROUBLE DIAGNOSIS FOR SELF-DIAGNOSTIC ITEMS
Revision: August 20072004 QX56
3. CHECK ICC STEERING SWITCH SIGNAL CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect connectors of ECM and spi INFINITI QX56 2004 Factory Service Manual ACS-42
[ICC]
TROUBLE DIAGNOSIS FOR SELF-DIAGNOSTIC ITEMS
Revision: August 20072004 QX56
3. CHECK ICC STEERING SWITCH SIGNAL CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect connectors of ECM and spi](/manual-img/42/57034/w960_57034-50.png)
ACS-42
[ICC]
TROUBLE DIAGNOSIS FOR SELF-DIAGNOSTIC ITEMS
Revision: August 20072004 QX56
3. CHECK ICC STEERING SWITCH SIGNAL CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect connectors of ECM and spiral cable.
3. Check continuity between ECM harness connectors E16 and
F54 terminals 67 (B), 99 (G/Y) and spiral cable M30 terminal 33
(B), 34 (G/Y).
OK or NG
OK >> GO TO 4.
NG >>
Repair harness between ECM and spiral cable.
Erase DTC and perform ICC system running test. Then, perform self-diagnosis of ICC system
again.
4. CHECK ICC STEERING SWITCH SIGNAL CIRCUIT
1. Disconnect remaining spiral cable connector.
2. Check continuity between spiral cable (to vehicle) harness con-
nector M30 terminal 33, 34 and spiral cable (to switch) harness
connector M102 terminal 14,15.
OK or NG
OK >> Replace ECM. Erase DTC and perform ICC system run-
ning test. Then perform self-diagnosis of ICC system
again.
NG >>
Replace spiral cable. Refer to SRS-47, "Removal
and Installation" .
Erase DTC and perform ICC system running test.
Then, perform self-diagnosis of ICC system again.
DTC 74 LASER BEAM OFF CENTEREKS007XE
1. DIAGNOSTIC CHECK
1. Adjust laser beam aiming. Then erase DTC, and perform ICC system running test. Refer to ACS-12,
"LASER BEAM AIMING ADJUSTMENT" .
2. After that, perform self-diagnosis of ICC system. Is DTC 74 LASER BEAM OFF CNTR indicated?
YES or NO
YES >>Replace ICC sensor and adjust laser beam aiming. Refer to ACS-59, "ICC Sensor" .
After that, erase DTC and perform ICC system running test. Then perform self-diagnosis of ICC
system again.
NO >> Inspection end.67 - 33, 99 - 34 Continuity should exist.
WKIA1928E
34 - 14, 33 - 15 Continuity should exist.
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ACS-58
[ICC]
ELECTRICAL COMPONENT INSPECTION
Revision: August 20072004 QX56
ELECTRICAL COMPONENT INSPECTIONPFP:00000
ICC Steering SwitchEKS007TT
1. Disconnect ICC steering switch.
2. Check resistance between M102 terminals 14 and 15 while
depressing each switch.
ICC Brake Switch and Stop Lamp SwitchEKS007TU
Check each switch after adjusting brake pedal. Refer to BR-6,
"BRAKE PEDAL" .
Parking Brake SwitchEKS007TX
Switch ConditionResistance [Ω]
(Approx.)
ON/OFF Depressed 0
Released 5,456
DISTANCE Depressed 741
Released 5,456
ACCEL/RES Depressed 2,586
Released 5,456
COAST/SET Depressed 1,406
Released 5,456
CANCEL Depressed 309
Released 5,456
WKIA1916E
Continuity
ICC brake switch Stop lamp switch
When brake pedal is depressed No Yes
When brake pedal is released Yes No
WKIA3405E
Continuity to ground
Parking brake pedal depressed Yes
Parking brake pedal released No
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REMOVAL AND INSTALLATION
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REMOVAL AND INSTALLATIONPFP:00000
ICC UnitEKS007TO
ICC SensorEKS007TP
CAUTION:
Perform the laser beam aiming procedure every time the ICC sensor is removed or installed.
ICC Steering SwitchEKS007TQ
Replace ICC steering switch as switch kit assembly. Refer to AV-47, "Removal and Installation of Steering
Wheel Audio Control Switches" .
WKIA1914E
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ATC-146
HEATER & COOLING UNIT ASSEMBLY
Revision: August 20072004 QX56
4. Remove the exhaust system. Refer to EX-3, "Removal and Installation" .
5. Disconnect the front heater hoses from the front heater core.
6. Disconnect the high/low pressure pipes from the front expansion valve.
7. Move the two front seats to the rearmost position on the seat track.
8. Remove the instrument panel and console panel. Refer to IP-10, "
INSTRUMENT PANEL ASSEMBLY" .
9. Remove the steering column. Refer to PS-10, "
Removal and Installation" .
10. Disconnect the instrument panel wire harness at the RH and LH in-line connector brackets, and the fuse
block (J/B) electrical connectors. Refer to PG-40, "
Harness Layout" .
11. Disconnect the steering member from each side of the vehicle body.
12. Remove the front heater and cooling unit assembly with it attached to the steering member, from the vehi-
cle.
CAUTION:
Use care not to damage the seats and interior trim panels when removing the front heater and
cooling unit assembly with it attached to the steering member.
13. Remove the front heater and cooling unit assembly from the steering member.
Installation
Installation is in the reverse order of removal.
CAUTION:
Replace the O-ring of the low-pressure pipe and high-pressure pipe with a new one, and apply
compressor oil to it when installing it.
After charging the refrigerant, check for leaks.
NOTE:
Fill the engine cooling system with the specified coolant mixture. Refer to MA-13, "REFILLING ENGINE
COOLANT" .
Recharge the A/C system. Refer to ATC-162, "Evacuating System and Charging Refrigerant" .
REAR HEATER AND COOLING UNIT ASSEMBLY
Removal
1. Discharge the refrigerant from the A/C system. Refer to ATC-162, "Discharging Refrigerant" .
2. Drain the coolant from the engine cooling system. Refer to MA-12, "
DRAINING ENGINE COOLANT" .
3. Disconnect the rear heater core hoses from the rear heater core.
4. Disconnect the rear A/C pipes from the rear expansion valve.
5. Remove the rear RH interior trim panel. Refer to EI-34,
"Removal and Installation" .
6. Disconnect the following electrical connectors:
Rear blower motor
Rear blower motor resistor
Rear air mix door motor
7. Disconnect the ducts from the rear heater and cooling unit
assembly.
8. Remove the rear heater and cooling unit assembly.
Installation
Installation is in the reverse order of removal.
CAUTION:
Replace the O-ring of the low-pressure pipe and high-pressure pipe with a new one, and apply
compressor oil to it when installing it.
After charging the refrigerant, check for leaks.
NOTE:
Fill the engine cooling system with the specified coolant mixture. Refer to MA-13, "REFILLING ENGINE
COOLANT" .
Recharge the A/C system. Refer to ATC-162, "Evacuating System and Charging Refrigerant" .
LJIA0021E
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ATC-150
DEFROSTER DOOR MOTOR
Revision: August 20072004 QX56
DEFROSTER DOOR MOTORPFP:27733
Removal and InstallationEJS002D8
Defroster Door Motor - Front Heater and Cooling Unit Assembly
REMOVAL
1. Remove the front heater and cooling unit assembly. Refer to ATC-145, "FRONT HEATER AND COOLING
UNIT ASSEMBLY" .
2. Remove the steering member from the front heater and cooling unit assembly.
3. Disconnect the defroster door motor electrical connector.
4. Remove the three screws and remove the defroster door motor.
INSTALLATION
Installation is in the reverse order of removal.
LJIA0139E
1. Front heater and cooling unit assembly 2. Intake door motor 3. Air mix door motor (driver)
4. Variable blower control 5. Air mix door motor (passenger) 6. Mode door motor
7. Defroster door motor
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INTAKE DOOR MOTOR
ATC-151
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Removal and InstallationEJS002D9
Intake Door Motor - Front Heater and Cooling Unit Assembly
REMOVAL
1. Remove the front heater and cooling unit assembly. Refer to ATC-145, "FRONT HEATER AND COOLING
UNIT ASSEMBLY" .
2. Remove the steering member from the front heater and cooling unit assembly.
3. Disconnect the intake door motor electrical connector.
4. Remove the three screws and remove the intake door motor.
INSTALLATION
Installation is in the reverse order of removal.
LJIA0139E
1. Front heater and cooling unit assembly 2. Intake door motor 3. Air mix door motor (driver)
4. Variable blower control 5. Air mix door motor (passenger) 6. Mode door motor
7. Defroster door motor
Page 557 of 3371
ATC-152
MODE DOOR MOTOR
Revision: August 20072004 QX56
MODE DOOR MOTORPFP:27731
Removal and InstallationEJS002DA
Mode Door Motor - Front Heater and Cooling Unit Assembly
REMOVAL
1. Remove the front heater and cooling unit assembly. Refer to ATC-145, "FRONT HEATER AND COOLING
UNIT ASSEMBLY" .
2. Remove the steering member from the front heater and cooling unit assembly.
3. Disconnect the mode door motor electrical connector.
4. Remove the two screws and remove the mode door motor.
INSTALLATION
Installation is in the reverse order of removal.
LJIA0139E
1. Front heater and cooling unit assembly 2. Intake door motor 3. Air mix door motor (driver)
4. Variable blower control 5. Air mix door motor (passenger) 6. Mode door motor
7. Defroster door motor