EC-374
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
P0603 ECM POWER SUPPLY
P0603 ECM POWER SUPPLY
DTC LogicINFOID:0000000006217873
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
1.PRECONDITIONING
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
>> GO TO 2.
2.PERFORM DTC CONFIRMATION PROCEDURE
1. Turn ignition switch ON wait at least 10 seconds.
2. Turn ignition switch OFF and wait at least 5 minutes.
3. Turn ignition switch ON, wait at least 10 seconds.
4. Repeat step 2 and 3 for five times.
5. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Go to EC-374, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006217874
1.CHECK ECM POWER SUPPLY
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check the voltage between ECM harness connector terminals.
Is the inspection result normal?
YES >> GO TO 3.
NO >> GO TO 2.
2.DETECT MALFUNCTIONING PART
Check the following.
20 A fuse (No. 43)
Harness for open or short between ECM and battery
Loose or poor connection for each connector and harness
>> Repair or replace harness or connectors.
3.CHECK INTERMITTENT INCIDENT
DTC No. Trouble diagnosis name
(Trouble diagnosis content) DTC detecting condition Possible cause
P0603 ECM BACK UP/CIRCUIT
(ECM power supply circuit) ECM back up RAM system does not
function properly. Harness or connectors
[ECM power supply (back up) circuit is open or
shorted.]
ECM
ECM
Vol tag e
+–
Connector Terminal Connector Terminal E80 156 E80 175 Battery voltage
Revision: 2010 May2011 QX56
P1220 FUEL PUMP CONTROL MODULE (FPCM)
EC-403
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
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P1220 FUEL PUMP CONTROL MODULE (FPCM)
DTC LogicINFOID:0000000006217912
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
1.PRECONDITIONING
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is between 12 - 15 V at idle.
Before performing the following procedure, check that the engine coolant temperature is −10 °C
(14 °F) or more.
>> GO TO 2.
2.PERFORM DTC CONFIRMATION PROCEDURE
1. Start engine and let it idle for at least 5 seconds. If engine does not start, crank engine for at least 5 seconds.
2. Check DTC.
Is DTC detected?
YES >> Go to EC-403, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006217913
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 >> GO TO 3.
2.DETECT MALFUNCTIONING PART
Check the following.
15 A fuse (No.73)
Harness for open or short between FPCM and IPDM E/R
Loose or poor connection for each connector and harness
>> Repair open circuit, short to ground or short to power in harness or connectors.
DTC No. Trouble diagnosis name
(Trouble diagnosis content) DTC detecting condition Possible cause
P1220 FPCM
(Fuel pump control module) During engine cranking, the signal voltage
of the FPCM to the ECM is too low. Harness or connectors
(FPCM circuit is open or shorted)
(Fuel pump circuit is open or shorted)
FPCM
FPCM Ground Voltage
Connector Terminal
B41 10 Ground Battery voltage
Revision: 2010 May2011 QX56
EC-440
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
P1572 ASCD BRAKE SWITCH
Is the inspection result normal?
YES >> GO TO 13.
NO >> GO TO 8.
3.CHECK ASCD BRAKE SWITCH POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect ASCD brake switch harness connector.
3. Turn ignition switch ON.
4. Check the voltage between ASCD brake switch harness connector and ground.
Is the inspection result normal?
YES >> GO TO 5.
NO >> GO TO 4.
4.DETECT MALFUNCTIONING PART
Check the following.
10 A fuse (No. 3)
Harness for open or short between ASCD brake switch and fuse
Loose or poor connection for each connector and harness
>> Repair open circuit or short to ground in harness or connectors.
5.CHECK ASCD BRAKE SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check the continuity between ASCD brake s witch harness connector and ECM harness connector.
4. Also check harness for short to ground and short to power.
Is the inspection result normal?
YES >> GO TO 7.
NO >> GO TO 6.
6.DETECT MALFUNCTIONING PART
Check the following.
Harness for open or short between ECM and ASCD brake switch
Loose or poor connection for each connector and harness
>> Repair open circuit, short to ground or short to power in harness or connectors.
7.CHECK ASCD BRAKE SWITCH
Refer to EC-442, "
Component Inspection (ASCD Brake Switch)"
Is the inspection result normal?
ECM
Condition Voltage (V)
Connector +–
Terminal Terminal
E80 158
(Stop lamp switch signal) 175 Brake pedalSlightly depressed Battery voltage
Fully released Approx. 0
ASCD brake switch
Ground Voltage
Connector Terminal
E109 1 Ground Battery voltage
ASCD brake switch ECM Continuity
Connector Terminal Connector Terminal
E109 2 E80 147 Existed
Revision: 2010 May2011 QX56
P1572 ASCD BRAKE SWITCHEC-441
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
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YES >> GO TO 13.
NO >> Replace ASCD brake switch.
8.CHECK STOP LAMP SWIT
CH POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect stop lamp switch harness connector.
3. Check the voltage between stop lamp switch harness connector and ground.
Is the inspection result normal?
YES >> GO TO 10.
NO >> GO TO 9.
9.DETECT MALFUNCTIONING PART
Check the following.
10 A fuse (No. 7)
Harness for open or short between stop lamp switch and battery
Loose or poor connection for each connector and harness
>> Repair open circuit, short to ground or short to power in harness or connectors.
10.CHECK STOP LAMP SWITCH INPUT SI GNAL CIRCUIT FOR OPEN AND SHORT
1. Disconnect ECM harness connector.
2. Check the continuity between stop lamp switch harness connector and ECM harness connector.
3. Also check harness for short to ground and short to power.
Is the inspection result normal?
YES >> GO TO 12.
NO >> GO TO 11.
11 .DETECT MALFUNCTIONING PART
Check the following.
Harness for open or short between ECM and stop lamp switch
Loose or poor connection for each connector and harness
>> Repair open circuit, short to ground or short to power in harness or connectors.
12.CHECK STOP LAMP SWITCH
Refer to EC-442, "
Component Inspection (Stop Lamp Switch)".
Is the inspection result normal?
YES >> GO TO 13.
NO >> Replace stop lamp switch.
13.CHECK INTERMITTENT INCIDENT
Refer to GI-40, "
Intermittent Incident".
>> INSPECTION END
Stop lamp switch Ground Voltage
Connector Terminal
E115 1 Ground Battery voltage
Stop lamp switch ECM Continuity
Connector Terminal Connector Terminal
E115 2 E80 158 Existed
Revision: 2010 May2011 QX56
P1572 ICC BRAKE SWITCHEC-445
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Is the inspection result normal?
YES >> GO TO 5.
NO >> GO TO 4.
4.DETECT MALFUNCTIONING PART
Check the following.
10 A fuse (No. 3)
Harness for open or short between ICC brake switch and fuse
Loose or poor connection for each connector and harness
>> Repair open circuit or short to ground in harness or connectors.
5.CHECK ICC BRAKE SWITCH INPUT SIGN AL CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check the continuity between ICC brake sw itch harness connector and ECM harness connector.
4. Also check harness for short to ground and short to power.
Is the inspection result normal?
YES >> GO TO 7.
NO >> GO TO 6.
6.DETECT MALFUNCTIONING PART
Check the following.
Harness for open or short between ICC brake switch and ECM
Loose or poor connection for each connector and harness
>> Repair open circuit, short to ground or short to power in harness or connectors.
7.CHECK ICC BRAKE SWITCH
Refer to EC-445, "
Component Inspection (ICC Brake Switch)".
Is the inspection result normal?
YES >> GO TO 8.
NO >> Replace ICC brake switch.
8.CHECK INTERMITTENT INCIDENT
Refer to GI-40, "
Intermittent Incident".
>> INSPECTION END
Component Inspection (ICC Brake Switch)INFOID:0000000006217949
1.CHECK ICC BRAKE SWITCH-I
1. Turn ignition switch OFF.
2. Disconnect ICC brake switch harness connector.
3. Check the continuity between ICC brake switch terminals under the following conditions.
Is the inspection result normal?
YES >> INSPECTION END
ICC brake switch ECM Continuity
Connector Terminal Connector Terminal
E68 2 E80 147 Existed
Terminals Condition Continuity
1 and 2 Brake pedal Fully released Existed
Slightly depressed Not existed
Revision: 2010 May2011 QX56
P1805 BRAKE SWITCHEC-455
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
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P1805 BRAKE SWITCH
DTC LogicINFOID:0000000006217957
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
1.PERFORM DTC CONFIRMATION PROCEDURE
1. Turn ignition switch ON.
2. Fully depress the brake pedal for at least 5 seconds.
3. Erase the DTC.
4. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Go to EC-455, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006217958
1.CHECK STOP LAMP SWITCH CIRCUIT
1. Turn ignition switch OFF.
2. Check for stop lamp illumination under the following conditions.
Is the inspection result normal?
YES >> GO TO 4.
NO >> GO TO 2.
2.CHECK STOP LAMP SWIT CH POWER SUPPLY CIRCUIT
1. Disconnect stop lamp switch harness connector.
2. Check the voltage between stop lamp 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.
10 A fuse (No. 7)
Harness for open or short between stop lamp switch and battery
Loose or poor connection for each connector and harness
>> Repair open circuit, short to ground or short to power in harness or connectors.
DTC No. Trouble diagnosis name
(Trouble diagnosis content) DTC detecting condition Possible cause
P1805 BRAKE SW/CIRCUIT
(Brake switch) A brake switch signal is not sent to ECM
for extremely long time while the vehicle
is being driven. Harness or connectors
(Stop lamp switch circuit is open or shorted.)
Stop lamp switch
Condition Stop lamp
Brake pedal Fully released Not illuminated
Slightly depressed Illuminated
Stop lamp switch Ground Voltage
Connector Terminal
E115 1 Ground Battery voltage
Revision: 2010 May2011 QX56
P2100, P2103 THROTTLE CONTROL MOTOR RELAY
EC-459
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NO >> GO TO 2.
2.DETECT MALFUNCTIONING PART
Check the following.
Harness for open or short between ECM and IPDM E/R
Loose or poor connection for each connector and harness
>> Repair open circuit, short to ground or short to power in harness or connectors.
3.CHECK THROTTLE CONTROL MOTO R RELAY INPUT SIGNAL CIRCUIT
1. Check the continuity between IPDM E/R s ensor harness connector and ECM harness connector.
2. Also check harness for short to ground and short to power.
Is the inspection result normal?
YES >> GO TO 5.
NO >> GO TO 4.
4.DETECT MALFUNCTIONING PART
Check the following.
Harness for open or short between ECM and IPDM E/R
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 FUSE
1. Disconnect 20 A fuse (No. 64) from IPDM E/R.
2. Check if 20 A fuse is blown.
Is the inspection result normal?
YES >> GO TO 6.
NO >> Replace 20 A fuse.
6.CHECK INTERMITTENT INCIDENT
Refer to GI-40, "
Intermittent Incident".
Is the inspection result normal?
YES >> Replace IPDM E/R. Refer to PCS-32, "Removal and Installation".
NO >> Repair or replace harness or connectors.
IPDM E/R ECM Continuity
Connector Terminal Connector Terminal
E15 55 E80 173 Existed
Revision: 2010 May2011 QX56
P2101 ELECTRIC THROTTLE CONTROL FUNCTIONEC-461
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
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2.CHECK THROTTLE CONTROL MOTO
R RELAY POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Disconnect IPDM E/R harness connector.
4. Check the continuity between ECM harne ss connector and IPDM E/R harness connector.
5. Also check harness for short to ground and short to power.
Is the inspection result normal?
YES >> GO TO 4.
NO >> GO TO 3.
3.DETECT MALFUNCTIONING PART
Check the following.
Harness for open or short between ECM and IPDM E/R
Loose or poor connection for each connector and harness
>> Repair open circuit or short to ground or short to power in harness or connectors.
4.CHECK THROTTLE CONTROL MOTOR RELAY INPUT SIGNAL CIRCUIT-II
1. Check the continuity between ECM harne ss connector and IPDM E/R harness connector.
2. Also check harness for short to ground and short to power.
Is the inspection result normal?
YES >> GO TO 6.
NO >> GO TO 5.
5.DETECT MALFUNCTIONING PART
Check the following.
Harness for open or short between ECM and IPDM E/R
Loose or poor connection for each connector and harness
>> Repair open circuit or short to ground or short to power in harness or connectors.
6.CHECK FUSE
1. Disconnect 20 A fuse (No. 64) from IPDM E/R.
2. Check 20 A fuse for blown.
Is the inspection result normal?
YES >> GO TO 7.
NO >> Replace 20 A fuse.
7.CHECK INTERMITTENT INCIDENT
Refer to GI-40, "
Intermittent Incident".
Is the inspection result normal?
YES >> Replace IPDM E/R. Refer to PCS-32, "Removal and Installation".
NO >> Repair or replace harness or connectors.
8.CHECK THROTTLE CONTROL MOTOR OUTPUT SIGNAL CIRCUIT FOR OPEN OR SHORT
1. Turn ignition switch OFF.
IPDM E/R ECM Continuity
Connector Terminal Connector Terminal
E15 60 E80 123 Existed
IPDM E/R ECM Continuity
Connector Terminal Connector Terminal
E15 55 E80 173 Existed
Revision: 2010 May2011 QX56