2009 INFINITI QX56 ignition

ICC BRAKE SWITCHEC-399
< COMPONENT DIAGNOSIS > [VK56DE]
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ICC BRAKE SWITCH
Component DescriptionINFOID:0000000003771718
When depress on the brake pedal, ICC brake switch is turned OFF
and stop lamp switch is turned ON. ECM detects the state of the
brake pedal by this input of two kinds (ON/OFF signal)
Refer to
CCS-13
for the ICC function.
Diagnosis ProcedureINFOID:0000000003771719
1.CHECK OVERALL FUNCTION-I
With CONSULT-IIl
1. Turn ignition switch ON.
2. Select “BRAKE SW1” in “DATA MONITOR” mode with CONSULT-IIl.
3. Check “BRAKE SW1” indication under the following conditions.
Without CONSULT-IIl
1. Turn ignition switch ON.
2. Check voltage between ECM terminal 108 and ground under the
following conditions.
OK or NG
OK >> GO TO 2.
NG >> GO TO 3.
2.CHECK OVERALL FUNCTION-II
With CONSULT-IIl
Check “BRAKE SW2” indication in “DATA MONITOR” mode.
Without CONSULT-IIl
BBIA0470E
CONDITION INDICATION
Brake pedal: Slightly depressed OFF
Brake pedal: Fully released ON
CONDITION VOLTAGE
Brake pedal: Slightly depressed Approximately 0V
Brake pedal: Fully released Battery voltage
MBIB0061E
CONDITION INDICATION
Brake pedal: Fully released OFF
Brake pedal: Slightly depressed ON
Revision: December 20092009 QX56

EC-400
< COMPONENT DIAGNOSIS >[VK56DE]
ICC BRAKE SWITCH
Check voltage between ECM terminal 101 and ground under the fol-
lowing conditions.
OK or NG
OK >>
INSPECTION END
NG >> GO TO 10.
3.CHECK DTC WITH ICC UNIT
Refer to CCS-18
.
OK or NG
OK >> GO TO 4.
NG >> Repair or replace.
4.CHECK ICC BRAKE HOLD RE LAY POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect ICC brake hold relay.
3. Turn ignition switch ON.
4. Check voltage between ICC brake hold relay terminal 4 and ground with CONSULT-IIl or tester.
OK or NG
OK >> GO TO 6.
NG >> GO TO 5.
5.DETECT MALFUNCTIONING PART
Check the following.
 Harness connectors M31, E152
 Fuse block (J/B) connector M4
 10A fuse
 Harness for open or short between ICC brake hold relay and fuse
>> Repair open circuit or short to ground or short to power in harness or connectors.
6.CHECK ICC BRAKE SWITCH POWER SUPPLY CIRCUIT
CONDITION VOLTAGE
Brake pedal: Fully released Approximately 0V
Brake pedal: Slightly depressed Battery voltage
PBIB1537E
BBIA0471E
Voltage: Battery voltage
MBIB0059E
Revision: December 20092009 QX56

ICC BRAKE SWITCHEC-401
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1. Turn ignition switch OFF.
2. Disconnect ICC brake switch harness connector.
3. Check harness continuity between ICC brake hold relay terminal
3 and ICC brake switch terminal 1.
Refer to Wiring Diagram.
4. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 7.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
7.CHECK ICC BRAKE SWITCH INPUT SIGN AL CIRCUIT FOR OPEN AND SHORT
1. Disconnect ECM harness connector.
2. Check harness continuity between ICC brake switch terminal 2 and ECM terminal 108. Refer Wiring Diagram.
3. 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 ICC BRAKE HOLD RELAY
Refer to EC-402, "Component Inspection"
.
OK >> GO TO 9.
NG >> Replace ICC brake hold relay.
9.CHECK ICC BRAKE SWITCH
Refer to EC-402, "Component Inspection"
.
OK or NG
OK >> GO TO 14.
NG >> Replace ICC brake switch.
10.CHECK STOP LAMP SWITCH POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect stop lamp switch harness connector. Continuity should exist.
BBIA0470E
Continuity should exist.
BBIA0470E
Revision: December 20092009 QX56

EC-402
< COMPONENT DIAGNOSIS >[VK56DE]
ICC BRAKE SWITCH
3. Check voltage between stop lamp switch terminal 3 and ground
with CONSULT -IIl or tester.
OK or NG
OK >> GO TO 12.
NG >> GO TO 11.
11 .DETECT MALFUNCTIONING PART
Check the following.
 Harness connectors M31, E152
 Fuse block (J/B) No. 1 connector M60
 10A fuse
 Harness for open or short between stop lamp switch and battery
>> Repair open circuit or short to ground or short to power in harness or connectors.
12.CHECK STOP LAMP SWITCH INPUT SI GNAL CIRCUIT FOR OPEN AND SHORT
1. Disconnect ECM harness connector.
2. Check harness continuity between ECM terminal 101 and stop lamp switch terminal 4. Refer to Wiring Diagram.
3. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 13.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
13.CHECK STOP LAMP SWITCH
Refer to EC-402, "Component Inspection"
.
OK or NG
OK >> GO TO 14.
NG >> Replace stop lamp switch.
14.CHECK INTERMITTENT INCIDENT
Refer to GI-35, "How to Check Terminal"
and GI-38, "Intermittent Incident".
>> INSPECTION END
Component InspectionINFOID:0000000003771720
ICC BRAKE SWITCH
1. Turn ignition switch OFF.
2. Disconnect ICC brake switch harness connector. Voltage: Battery voltage
PBIB2102E
Continuity should exist.
Revision: December 20092009 QX56

ICC BRAKE SWITCHEC-403
< COMPONENT DIAGNOSIS > [VK56DE]
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3. Check continuity between ICC brake switch terminals 1 and 2
under the following conditions.
If NG, adjust ICC brake switch installation, refer to BR-15,
"Inspection and Adjustment" , and perform step 3 again.
STOP LAMP SWITCH
1. Turn ignition switch OFF.
2. Disconnect stop lamp switch harness connector.
3. Check continuity between stop lamp switch terminals 3 and 4
under the following conditions.
If NG, adjust stop lamp switch installation, refer to BR-15,
"Inspection and Adjustment", and perform step 3 again.
ICC BRAKE HOLD RELAY
1. Apply 12V direct current between ICC brake hold relay terminals 1 and 2.
2. Check continuity between relay terminals 3 and 4, 6 and 7 under
the following conditions.
3. If NG, replace ICC brake hold relay.
Condition Continuity
Brake pedal: Fully released. Should exist.
Brake pedal: Slightly depressed. Should not exist.
PBIB1536E
Condition Continuity
Brake pedal: Fully released. Should not exist.
Brake pedal: Slightly depressed. Should exist.
PBIB2103E
Condition Between terminals Continuity
12V direct current supply
between terminals 1 and 2 3 and 4 Should not exist
6 and 7 Should exist
No current supply 3 and 4 Should exist
6 and 7 Should not exist
MBIB0063E
Revision: December 20092009 QX56

EC-404
< COMPONENT DIAGNOSIS >[VK56DE]
IGNITION SIGNAL
IGNITION SIGNAL
Component DescriptionINFOID:0000000003771721
IGNITION COIL & POWER TRANSISTOR
The ignition signal from the ECM is sent to and amplifi
ed by the power transistor. The power transistor turns
ON and OFF the ignition coil primary circuit. This ON/O FF operation induces the proper high voltage in the coil
secondary circuit.
Diagnosis ProcedureINFOID:0000000003771722
1.CHECK ENGINE START
Turn ignition switch OFF, and restart engine.
Is engine running?
Ye s o r N o
Yes (With CONSULT-IIl)>>GO TO 2.
Yes (Without CONSULT-lII)>>GO TO 3.
No >> GO TO 4.
2.CHECK OVERALL FUNCTION
With CONSULT-IIl
1. Perform “POWER BALANCE” in “ACTIVE TEST” mode with CONSULT-lII.
2. Make sure that each circuit produces a momentary engine speed drop.
OK or NG
OK >> INSPECTION END
NG >> GO TO 10.
3.CHECK OVERALL FUNCTION
Without CONSULT-IIl
1. Let engine idle.
2. Read the voltage signal between ECM terminals 46, 60, 61, 62, 65, 79, 80, 81 and ground with an oscilloscope.
3. Verify that the oscilloscope screen shows the signal wave as shown below.
NOTE:
The pulse cycle changes depending on rpm at idle.
OK or NG
1. Ignition coils (with power transistor) (bank 2) 2. Ignition coils (with power transistor)
(bank 1)
BBIA0777E
PBIB2094E
PBIB0044E
Revision: December 20092009 QX56

IGNITION SIGNALEC-405
< COMPONENT DIAGNOSIS > [VK56DE]
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OK >>
INSPECTION END
NG >> GO TO 10.
4.CHECK IGNITION COIL POWER SUPPLY CIRCUIT-I
1. Turn ignition switch OFF, wait at least 10 seconds and then turn ON.
2. Check voltage between ECM terminals 119, 120 and ground with CONSULT-IIl or tester.
OK or NG
OK >> GO TO 5.
NG >> Go to EC-82
.
5.CHECK IGNITION COIL POWER SUPPLY CIRCUIT-II
1. Turn ignition switch OFF.
2. Disconnect condenser-1 harness connector.
3. Turn ignition switch ON.
4. Check voltage between condenser-1 terminal 1 and ground with CONSULT-IIl or tester.
OK or NG
OK >> GO TO 8.
NG >> GO TO 6.
6.CHECK IGNITION COIL POWER SUPPLY CIRCUIT-III
1. Turn ignition switch OFF.
2. Disconnect IPDM E/R connector E119.
3. Check harness continuity between IPDM E/R terminal 4 and condenser-1 terminal 1. Refer to Wiring Diagram.
4. Also check harness for short to ground and short to power.
OK or NG
OK >> Go to EC-82.
NG >> GO TO 7.
7.DETECT MALFUNCTIONING PART
Check the following.
 Harness connectors E2, F32 Voltage: Battery voltage
MBIB0034E
BBIA0358E
Voltage: Battery voltage
PBIB0624E
Continuity should exist.
Revision: December 20092009 QX56

EC-406
< COMPONENT DIAGNOSIS >[VK56DE]
IGNITION SIGNAL
 Harness for open or short between condenser-1 and IPDM E/R
>> Repair open circuit or short to ground or short to power in harness or connectors.
8.CHECK CONDENSER-1 GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Check harness continuity between condenser-1 terminal 2 and ground. Refer to Wiring Diagram.
3. Also check harness for short to power.
OK or NG
OK >> GO TO 9.
NG >> Repair open circuit or short to power in harness or connectors.
9.CHECK CONDENSER-1
Refer to EC-407, "Component Inspection"
.
OK or NG
OK >> GO TO 10.
NG >> Replace condenser-1.
10.CHECK IGNITION COIL POWER SUPPLY CIRCUIT-IV
1. Turn ignition switch OFF.
2. Reconnect all harness connectors disconnected.
3. Disconnect ignition coil harness connector.
4. Turn ignition switch ON.
5. Check voltage between ignition coil terminal 3 and ground with CONSULT-IIl or tester.
OK or NG
OK >> GO TO 12.
NG >> GO TO 11.
11 .DETECT MALFUNCTIONING PART
Check the following.
 Harness connectors E2, F32
 Harness for open or short between ignition coil and harness connector F32 Continuity should exist.
1. Ignition coils (with power transistor)
(bank 2) 2. Ignition coils (with power transistor)
(bank 1)
Voltage: Battery voltage
BBIA0777E
PBIB0138E
Revision: December 20092009 QX56