diagram INFINITI QX56 2004 Factory Owners Manual

DTC P0117, P0118 ECT SENSOR
EC-167
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EC
Revision: August 20072004 QX56
Wiring DiagramUBS00H1M
BBWA11 61 E

DTC P0117, P0118 ECT SENSOR
EC-169
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EC
Revision: August 20072004 QX56
4. CHECK ECT SENSOR GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check harness continuity between ECT sensor terminal 2 and ECM terminal 67.
Refer to Wiring Diagram.
4. Also check harness for short to ground or short to power.
OK or NG
OK >> GO TO 6.
NG >> GO TO 5.
5. DETECT MALFUNCTIONING PART
Check the following.

Harness connector F26, F101

Harness for open and short between ECT sensor and ECM
>> Repair open circuit or short to ground or short to power in harness or connectors.
6. CHECK ENGINE COOLANT TEMPERATURE SENSOR
Refer to EC-169, "
Component Inspection" .
OK or NG
OK >> GO TO 7.
NG >> Replace engine coolant temperature sensor.
7. CHECK INTERMITTENT INCIDENT
Refer to EC-127, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
>>INSPECTION END
Component InspectionUBS00H1O
ENGINE COOLANT TEMPERATURE SENSOR
1. Check resistance between engine coolant temperature sensor
terminals 1 and 2 as shown in the figure.Continuity should exist.
PBIB0081E

DTC P0122, P0123 TP SENSOR
EC-173
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MA
EC
Revision: August 20072004 QX56
Wiring DiagramUBS00H1U
BBWA11 67 E

DTC P0122, P0123 TP SENSOR
EC-175
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EC
Revision: August 20072004 QX56
2. CHECK THROTTLE POSITION SENSOR 2 POWER SUPPLY CIRCUIT-I
1. Disconnect electric throttle control actuator harness connector.
2. Turn ignition switch ON.
3. Check voltage between electric throttle control actuator terminal
2 and ground with CONSULT-II or tester.
OK or NG
OK >> GO TO 7.
NG >> GO TO 3.
3. CHECK THROTTLE POSITION SENSOR 2 POWER SUPPLY CIRCUIT-II
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check harness continuity between electric throttle control actuator terminal 2 and ECM terminal 47.
Refer to Wiring Diagram.
OK or NG
OK >> GO TO 4.
NG >> Repair or replace open circuit.
4. CHECK THROTTLE POSITION SENSOR 2 POWER SUPPLY CIRCUIT-II
Check the following.

Harness for short to power and short to ground, between the following terminals.
OK or NG
OK >> GO TO 5.
NG >> Repair short to ground or short to power in harness or connectors.
5. CHECK ACCELERATOR PEDAL POSITION SENSOR
Refer to EC-568, "
Component Inspection" .
OK or NG
OK >> GO TO 11.
NG >> GO TO 6.
PBIB1480E
Voltage: Approximately 5V
PBIB2065E
Continuity should exist.
ECM terminal Sensor terminal Reference Wiring Diagram
47 Electric throttle control actuator terminal 2EC-173
91 APP sensor terminal 6EC-564

EC-176Revision: August 2007
DTC P0122, P0123 TP SENSOR
2004 QX56
6. REPLACE ACCELERATOR PEDAL ASSEMBLY
1. Replace the accelerator pedal assembly.
2. Perform EC-44, "
Accelerator Pedal Released Position Learning" .
3. Perform EC-44, "
Throttle Valve Closed Position Learning" .
4. Perform EC-44, "
Idle Air Volume Learning" .
>>INSPECTION END
7. CHECK THROTTLE POSITION SENSOR 2 GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check harness continuity between electric throttle control actuator terminal 4 and ECM terminal 66.
Refer to Wiring Diagram.
4. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 8.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
8. CHECK THROTTLE POSITION SENSOR 2 INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Check harness continuity between ECM terminal 69 and electric throttle control actuator terminal 3.
Refer to Wiring Diagram.
2. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 9.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
9. CHECK THROTTLE POSITION SENSOR
Refer to EC-177, "
Component Inspection" .
OK or NG
OK >> GO TO 11.
NG >> GO TO 10.
10. REPLACE ELECTRIC THROTTLE CONTROL ACTUATOR
1. Replace the electric throttle control actuator.
2. Perform EC-44, "
Throttle Valve Closed Position Learning" .
3. Perform EC-44, "
Idle Air Volume Learning" .
>>INSPECTION END
11 . CHECK INTERMITTENT INCIDENT
Refer to EC-127, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
>>INSPECTION END Continuity should exist.
Continuity should exist.

EC-188Revision: August 2007
DTC P0138, P0158 HO2S2
2004 QX56
Wiring DiagramUBS00H2J
BANK 1
BBWA11 58 E

EC-192Revision: August 2007
DTC P0138, P0158 HO2S2
2004 QX56
2. CHECK HO2S2 GROUND CIRCUIT FOR OPEN AND SHORT
1. Disconnect heated oxygen sensor 2 harness connector.
2. Check harness continuity between HO2S2 terminal 4 and body ground.
Refer to Wiring Diagram.
3. Also check harness for short to power.
OK or NG
OK >> GO TO 4.
NG >> GO TO 3.
3. DETECT MALFUNCTIONING PART
Check the following.

Harness connectors E5, F14

Harness for open or short between heated oxygen sensor 2 and body ground
>> Repair open circuit or short to power in harness or connectors. Continuity should exist.
BBIA0435E

DTC P0138, P0158 HO2S2
EC-193
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EC
Revision: August 20072004 QX56
4. CHECK HO2S2 INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Disconnect ECM harness connector.
2. Check harness continuity between ECM terminal and HO2S2 terminal as follows.
Refer to Wiring Diagram.
3. Check harness continuity between the following terminals and ground.
Refer to Wiring Diagram.
4. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 5.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
5. CHECK HO2S2 CONNECTOR FOR WATER
1. Turn ignition switch OFF.
2. Disconnect heated oxygen sensor 2 harness connector.
3. Check connectors for water.
OK or NG
OK >> GO TO 6.
NG >> Repair or replace harness or connectors.
6. CHECK HEATED OXYGEN SENSOR 2
Refer to EC-194, "
Component Inspection" .
OK or NG
OK >> GO TO 7.
NG >> Replace malfunctioning heated oxygen sensor 2.
7. CHECK INTERMITTENT INCIDENT
Refer to EC-127, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
>>INSPECTION END
DTCTe r m i n a l s
Bank
ECM Sensor
P0138 55 1 1
P0158 74 1 2
Continuity should exist.
DTCTe r m i n a l s
Bank
ECM Sensor
P0138 55 1 1
P0158 74 1 2
Continuity should not exist.
Water should not exist.

DTC P0139, P0159 HO2S2
EC-199
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EC
Revision: August 20072004 QX56
Wiring DiagramUBS00H2S
BANK 1
BBWA11 58 E

EC-204Revision: August 2007
DTC P0139, P0159 HO2S2
2004 QX56
3. CHECK HO2S2 GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect heated oxygen sensor 2 harness connector.
3. Check harness continuity between HO2S2 terminal 4 and body ground.
Refer to Wiring Diagram.
4. Also check harness for short to power.
OK or NG
OK >> GO TO 5.
NG >> GO TO 4.
4. DETECT MALFUNCTIONING PART
Check the following.

Harness connectors E5, F14

Harness for open or short between heated oxygen sensor 2 and body ground
>> Repair open circuit or short to power in harness or connectors. Continuity should exist.
BBIA0435E