EC-504
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
ICC BRAKE SWITCH
Is the inspection result normal?
YES >> INSPECTION END
NO >> GO TO 3.
3.CHECK ICC BRAKE SWITCH POWER SUPPLY CIRCUIT-I
1. Turn ignition switch OFF.
2. Disconnect ICC brake switch harness connector.
3. Turn ignition switch ON.
4. Check the voltage between ICC brake switch harness connector and ground.
Is the inspection result normal?
YES >> GO TO 7.
NO >> GO TO 4.
4.CHECK ICC BRAKE SWITCH POWER SUPPLY CIRCUIT-II
Check the voltage between ICC brake switch harness connector and ground.
Is the inspection result normal?
YES >> GO TO 6.
NO >> GO TO 5.
5.DETECT MALFUNCTIONING PART
Check the following.
Fuse block (J/B) connector E103
10 A fuse (No. 3)
Harness for open or short between ICC brake switch and fuse
>> Repair open circuit or short to ground in harness or connectors.
6.CHECK ICC BRAKE SWITCH
Refer to EC-445, "
Component Inspection (ICC Brake Switch)".
Is the inspection result normal?
YES >> GO TO 9.
NO >> Replace ICC brake switch. Refer to BR-20, "
Removal and Installation".
7.CHECK ICC BRAKE SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check the continuity between ICC brake s witch harness connector and ECM harness connector.
ECM
Condition Voltage (V)
Connector +–
Te r m i n a l Te r m i n a l
E80 147
(ICC brake switch signal) 175 Brake pedalSlightly depressed Approx. 0
Fully released Battery voltage
ICC brake switch
Ground Voltage
Connector Terminal
E68 2 Ground Battery voltage
ICC brake switch Ground Voltage
Connector Terminal
E68 1 Ground Battery voltage
Revision: 2010 May2011 QX56
IGNITION SIGNALEC-507
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
C
D
E
F
G H
I
J
K L
M A
EC
NP
O
Is the inspection result normal?
YES >> GO TO 2.
NO >> Go to
EC-168, "
Diagnosis Procedure".
2.CHECK IGNITION COIL POWER SUPPLY CIRCUIT-II
1. Turn ignition switch OFF.
2. Disconnect condenser harness connector.
3. Turn ignition switch ON.
4. Check the voltage between condenser harness connector and ground.
Is the inspection result normal?
YES >> GO TO 5.
NO >> GO TO 3.
3.CHECK IGNITION COIL POWER SUPPLY CIRCUIT-III
1. Turn ignition switch OFF.
2. Disconnect IPDM E/R harness connector E7.
3. Check the continuity between IPDM E/R harness connector and condenser harness connector.
4. Also check harness for short to ground and short to power.
Is the inspection result normal?
YES >> Go to EC-168, "Diagnosis Procedure".
NO >> GO TO 4.
4.DETECT MALFUNCTIONING PART
Check the following.
Harness for open or short between IPDM E/R and condenser
Loose or poor connection for each connector and harness
>> Repair open circuit, short to ground or short to power in harness or connectors.
5.CHECK CONDENSER GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Check the continuity between condenser harness connector and ground.
3. Also check harness for short to power.
Is the inspection result normal?
ECM
Vo l ta g e
Connector +–
Terminal Terminal
E80 171
175 Battery voltage
172
Condenser Ground Voltage
Connector Terminal
F8 1 Ground Battery voltage
IPDM E/R Condenser Continuity
Connector Terminal Connector Terminal
E15 61 F8 1 Existed
Condenser Ground Continuity
Connector Terminal
F8 2 Ground Existed
Revision: 2010 May2011 QX56
EC-508
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
IGNITION SIGNAL
YES >> GO TO 6.
NO >> Repair open circuit or short to power in harness or connectors.
6.CHECK CONDENSER
Refer to EC-510, "
Component Inspection (Condenser)"
Is the inspection result normal?
YES >> GO TO 7.
NO >> Replace condenser.
7.CHECK IGNITION COIL POWER SUPPLY CIRCUIT-IV
1. Reconnect all harness connectors disconnected.
2. Disconnect ignition coil harness connector.
3. Turn ignition switch ON.
4. Check the voltage between ignition coil harness connector and ground.
Is the inspection result normal?
YES >> GO TO 9.
NO >> GO TO 8.
8.DETECT MALFUNCTIONING PART
Check the following.
Harness connector F22 and E46
Harness for open or short between ignition coil and harness connector F22
>> Repair or replace harness or connectors.
9.CHECK IGNITION COIL GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Check the continuity between ignition coil harness connector and ground.
3. Also check harness for short to power.
Is the inspection result normal?
Ignition coil Ground Voltage
Cylinder Connector Terminal
1F75 3
Ground Battery voltage
2F76 3
3F77 3
4F78 3
5F79 3
6F80 3
7F81 3
8F82 3
Ignition coil
Ground Continuity
Cylinder Connector Terminal
1F75 2
Ground Existed
2F76 2
3F77 2
4F78 2
5F79 2
6F80 2
7F81 2
8F82 2
Revision: 2010 May2011 QX56
EC-512
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
LOW PRESSURE FUEL PUMP
LOW PRESSURE FUEL PUMP
Component Function CheckINFOID:0000000006218017
1.CHECK FUEL PUMP FUNCTION
1. Turn ignition switch ON.
2. Pinch fuel feed hose with two fingers. NOTE:
Fuel pressure pulsation should be felt on the fuel feed hose for 1 second after ignition switch is turned ON.
Is the inspection result normal?
YES >> INSPECTION END
NO >> EC-512, "
Diagnosis Procedure".
Diagnosis ProcedureINFOID:0000000006218018
1.CHECK FPCM POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect FPCM harness connector.
3. Turn ignition switch ON.
4. Check the voltage between FPCM harness connector and ground.
Is the inspection result normal?
YES >> GO TO 2.
NO >> Perform the trouble diagnosis for power supply circuit. Refer to EC-168, "
Diagnosis Procedure".
2.CHECK FPCM GROUND CIRCUIT
1. Turn ignition switch OFF.
2. Check the continuity between FPCM harness connector and ground.
Is the inspection result normal?
YES >> GO TO 3.
NO >> Repair open circuit or short to power in harness or connectors.
3.CHECK FPCM INPUT AND OUTPUT CIRCUIT
1. Disconnect ECM harness connector.
2. Check the continuity between FPCM harness connector and ECM harness connector.
3. Also check harness for short to ground and to power.
Is the inspection result normal?
+ −Voltag e
FPCM
Connector Terminal B41 10 Ground Battery voltage
+ −Continuity
FPCM
Connector Terminal B41 5 Ground Existed
+ −
Continuity
FPCM ECM
Connector Terminal Connector Terminal
B41 8
E80 125
Existed
9142
Revision: 2010 May2011 QX56
EC-522
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
SNOW MODE SWITCH
SNOW MODE SWITCH
DescriptionINFOID:0000000006256403
The snow mode switch signal is sent to the combinat
ion meter from the snow mode switch. The combination
meter then sends the signal to the ECM via the CAN communication line.
The snow mode is used for driving or starting the vehicle on snowy roads or slippery areas. If the snow mode
is activated, the vehicle speed will not accelerate as quickly as normal to avoid vehicle slip. In other words,
ECM controls rapid engine torque change by controlling t he electric throttle control actuator operating speed.
Component Function CheckINFOID:0000000006256404
1.CHECK SNOW MODE SWITCH FUNCTION
1. Turn ignition switch ON.
2. Select “SNOW MODE SW” in “DATA MONITOR” mode with CONSULT-III.
3. Check “SNOW MODE SW” indication under the following conditions.
Is the inspection result normal?
YES >> INSPECTION END
NO >> Go to EC-522, "
Diagnosis Procedure".
Diagnosis ProcedureINFOID:0000000006256405
1.CHECK DTC WITH COMBINATION METER
Refer to MWI-30, "
CONSULT-III Function".
Is the inspection result normal?
YES >> GO TO 2.
NO >> Go to MWI-57, "
Work flow".
2.CHECK SNOW MODE SWITCH POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect snow mode switch harness connector.
3. Turn ignition switch ON.
4. Check the voltage between snow mode switch harness connector and ground.
Is the inspection result normal?
YES >> GO TO 4.
NO >> GO TO 3.
3.DETECT MALFUNCTIONING PART
Check the following.
Fuse block harness connector M3
10 A fuse (No. 13)
Harness for open or short between snow mode switch and fuse.
>> Repair open circuit, short to ground or short to power in harness or connectors.
4.CHECK SNOW MODE SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
Monitor item Condition Indication
SNOW MODE SW Snow mode switch ON ON
OFF OFF
Snow mode switch
Ground Voltage
Connector Terminal
M54 12 Ground Battery voltage
Revision: 2010 May2011 QX56
EC-524
< SYMPTOM DIAGNOSIS >[VK56VD]
ENGINE CONTROL SYSTEM SYMPTOMS
SYMPTOM DIAGNOSIS
ENGINE CONTROL SYSTEM SYMPTOMS
Symptom TableINFOID:0000000006218028
SYSTEM — BASIC ENGINE CONTROL SYSTEM
SYMPTOM
Reference
page
HARD/NO START/RESTART (EXCP. HA)
ENGINE STALL
HESITATION/SURGING/FLAT SPOT
SPARK KNOCK/DETONATION
LACK OF POWER/POOR ACCELERATION
HIGH IDLE/LOW IDLE
ROUGH IDLE/HUNTING
IDLING VIBRATION
SLOW/NO RETURN TO IDLE
OVERHEATS/WATER TEMPERATURE HIGH
EXCESSIVE FUEL CONSUMPTION
EXCESSIVE OIL CONSUMPTION
BATTERY DEAD (UNDER CHARGE)
Warranty symptom code AA AB AC AD AE AF AG AH AJ AK AL AM HA
Fuel Low pressure fuel pump circuit 11232 22 3 2 EC-512
Low fuel pressure sensor circuit 4 4EC-483
Fuel pressure regulator system 334444444 4EC-198
Fuel injector circuit 11232 22 2EC-498
Evaporative emission system 334444444 4EC-532
FRP sensor circuit 11222 22 2EC-276EC-279
High pressure fuel pump circuit 4 3
EC-501
Air Positive crankcase ventilation sys-
tem 334444444 41
EC-534
Incorrect idle speed adjustment 1 1 1 1 1 EC-139
Electric throttle control actuator 112332222 2 2EC-460EC-466
IgnitionIncorrect ignition timing adjustment33111 11 1
EC-139
Ignition circuit 11222 22 2EC-506
Main power supply and ground circuit 22333 33 23 EC-168
Revision: 2010 May2011 QX56
ENGINE CONTROL SYSTEM SYMPTOMSEC-525
< SYMPTOM DIAGNOSIS > [VK56VD]
C
D
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EC
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Mass air flow sensor circuit
1
12 2
222 2 EC-201
Engine coolant temperature sensor circuit
333
EC-217
Air fuel ratio (A/F) sensor 1 circuit EC-181
EC-228
EC-232
EC-235
EC-238
Throttle position sensor circuit
22EC-219
EC-288
EC-406
EC-407
EC-475
Accelerator pedal position sensor circuit 3 2 1
EC-468EC-471
EC-478
Knock sensor circuit 2 3
EC-297
Engine oil temperature sensor 4 2 3EC-285
Crankshaft position sensor circuit 2 2EC-299
Camshaft position sensor circuit 3 2EC-303
Vehicle speed signal circuit 2 3 3 3EC-356
Power steering pressure sensor circuit 2 3 3EC-371
ECM 22333333333EC-376EC-378
EC-380
Intake valve timing control solenoid valve cir-
cuit
32 13223 3
EC-193
VVEL control module 3 4 4 3 EC-451EC-452
VVEL actuator motor 3 4 4 3
EC-390
VVEL actuator motor relay 3 4 4 3EC-393
VVEL control shaft position sensor 3 4 4 3EC-387
PNP signal circuit 3 3 3 3 3EC-383
Refrigerant pressure sensor circuit 2 3 3 4EC-520
Electrical load signal circuit 3EC-493
Air conditioner circuit 223333333 3 2HAC-60
ABS actuator and electric unit (control unit) 4BRC-60
SYMPTOM
Reference
page
HARD/NO START/RESTART (EXCP. HA)
ENGINE STALL
HESITATION/SURGING/FLAT SPOT
SPARK KNOCK/DETONATION
LACK OF POWER/POOR ACCELERATION
HIGH IDLE/LOW IDLE
ROUGH IDLE/HUNTING
IDLING VIBRATION
SLOW/NO RETURN TO IDLE
OVERHEATS/WATER TEMPERATURE HIGH
EXCESSIVE FUEL CONSUMPTION
EXCESSIVE OIL CONSUMPTION
BATTERY DEAD (UNDER CHARGE)
Warranty symptom code AA AB AC AD AE AF AG AH AJ AK AL AM HA
Revision: 2010 May2011 QX56
EC-526
< SYMPTOM DIAGNOSIS >[VK56VD]
ENGINE CONTROL SYSTEM SYMPTOMS
1 - 6: The numbers refer to the order of inspection.
(continued on next page)
SYSTEM — ENGINE MECHANICAL & OTHER
Manifold absolute pressure sensor circuit 3
EC-210
Battery current sensor 4 5 5 3EC-412EC-420
EC-424
Heated oxygen sensor 2 6 6 6 6 5EC-243EC-249
EC-257
SYMPTOM
Reference
page
HARD/NO START/RESTART (EXCP. HA)
ENGINE STALL
HESITATION/SURGING/FLAT SPOT
SPARK KNOCK/DETONATION
LACK OF POWER/POOR ACCELERATION
HIGH IDLE/LOW IDLE
ROUGH IDLE/HUNTING
IDLING VIBRATION
SLOW/NO RETURN TO IDLE
OVERHEATS/WATER TEMPERATURE HIGH
EXCESSIVE FUEL CONSUMPTION
EXCESSIVE OIL CONSUMPTION
BATTERY DEAD (UNDER CHARGE)
Warranty symptom code AA AB AC AD AE AF AG AH AJ AK AL AM HA
SYMPTOM
Reference
page
HARD/NO START/RESTART (EXCP. HA)
ENGINE STALL
HESITATION/SURGING/FLAT SPOT
SPARK KNOCK/DETONATION
LACK OF POWER/POOR ACCELERATION
HIGH IDLE/LOW IDLE
ROUGH IDLE/HUNTING
IDLING VIBRATION
SLOW/NO RETURN TO IDLE
OVERHEATS/WATER TEMPERATURE HIGH
EXCESSIVE FUEL CONSUMPTION
EXCESSIVE OIL CONSUMPTION
BATTERY DEAD (UNDER CHARGE)
Warranty symptom code AA AB AC AD AE AF AG AH AJ AK AL AM HA
Fuel Fuel tank 5
5 FL-4
Fuel piping 555 55 5
FL-4
Vapor lock —
Valve deposit 5 555 55 5 —
Poor fuel (Heavy weight gasoline,
Low octane) —
Revision: 2010 May2011 QX56