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![INFINITI QX56 2008 Factory Service Manual EC-342
< COMPONENT DIAGNOSIS >[VK56DE]
P1572 ICC BRAKE SWITCH
5. Check 1st trip DTC.
6. If 1st trip DTC is detected, go to
EC-342, "
Diagnosis Procedure".
If 1st trip DTC is not detec ted, go to the INFINITI QX56 2008 Factory Service Manual EC-342
< COMPONENT DIAGNOSIS >[VK56DE]
P1572 ICC BRAKE SWITCH
5. Check 1st trip DTC.
6. If 1st trip DTC is detected, go to
EC-342, "
Diagnosis Procedure".
If 1st trip DTC is not detec ted, go to the](/manual-img/42/57030/w960_57030-1640.png)
EC-342
< COMPONENT DIAGNOSIS >[VK56DE]
P1572 ICC BRAKE SWITCH
5. Check 1st trip DTC.
6. If 1st trip DTC is detected, go to
EC-342, "
Diagnosis Procedure".
If 1st trip DTC is not detec ted, go to the following step.
7. Drive the vehicle for at least 5 consecutive seconds under the following conditions.
8. Check 1st trip DTC.
9. If 1st trip DTC is detected, go to EC-342, "
Diagnosis Procedure".
WITH GST
Follow the procedure “WITH CONSULT-IIl” above.
Diagnosis ProcedureINFOID:0000000001365771
1.CHECK OVERALL FUNCTION-I
With CONSULT-IIl
1. Turn ignition switch ON.
2. Select “BRAKE SW1” in “DAT A 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.
VHCL SPEED SE More than 30 km/h (19 MPH)
Selector lever Suitable position
VHCL SPEED SE More than 30 km/h (19 MPH)
Selector lever Suitable position
Driving location Depress the brake pedal for more than
five seconds so as not to come off from
the above-mentioned vehicle speed.
CONDITION
INDICATION
Brake pedal: Slightly depressed OFF
Brake pedal: Fully released ON
CONDITIONVOLTAGE
Brake pedal: Slightly depressed Approximately 0V
Brake pedal: Fully released Battery voltage
MBIB0061E
CONDITIONINDICATION
Brake pedal: Fully released OFF
Brake pedal: Slightly depressed ON
Revision: March 2010 2008 QX56
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![INFINITI QX56 2008 Factory Service Manual P1572 ICC BRAKE SWITCHEC-343
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Without CONSULT-IIl
Check voltage between ECM terminal 101 and ground under the fol-
lowing conditions.
INFINITI QX56 2008 Factory Service Manual P1572 ICC BRAKE SWITCHEC-343
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Without CONSULT-IIl
Check voltage between ECM terminal 101 and ground under the fol-
lowing conditions.](/manual-img/42/57030/w960_57030-1641.png)
P1572 ICC BRAKE SWITCHEC-343
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Without CONSULT-IIl
Check voltage between ECM terminal 101 and ground under the fol-
lowing conditions.
OK or NG
OK >> GO TO 14.
NG >> GO TO 7.
3.CHECK ICC BRAKE SWITCH POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect ICC brake switch harness connector.
3. Turn ignition switch ON.
4. Check voltage between ICC brake switch terminal 1 and ground with CONSULT-lll or tester.
OK or NG
OK >> GO TO 5.
NG >> GO TO 4.
4.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 switch and fuse
>> Repair open circuit or short to ground or short to power in harness or connectors.
5.CHECK ICC BRAKE SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check harness continuity between ICC brake switch terminal 2 and ECM terminal 108. Refer Wiring Diagram.
4. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 6.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
6.CHECK ICC BRAKE SWITCH
Refer to EC-346, "
Component Inspection".
OK or NG
OK >> GO TO 14.
NG >> Replace ICC brake switch.
CONDITION VOLTAGE
Brake pedal: Fully released Approximately 0V
Brake pedal: Slightly depressed Battery voltage
PBIB1537E
Voltage: Battery voltage
BBIA0470E
Continuity should exist.
Revision: March 2010 2008 QX56
Page 1643 of 4083
EC-344
< COMPONENT DIAGNOSIS >[VK56DE]
P1572 ICC BRAKE SWITCH
7.CHECK DTC WITH ICC UNIT
Refer to CCS-18
.
OK or NG
OK >> GO TO 8.
NG >> Repair or replace.
8.CHECK POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect stop lamp switch harness connector.
3. Check voltage between stop lamp switch terminal 3 and ground with CONSULT -IIl or tester.
4. Disconnect ICC brake hold relay.
5. Check voltage between ICC brake hold relay terminal 7 and ground with CONSULT-IIl or tester.
OK or NG
OK >> GO TO 10.
NG >> GO TO 9.
9.DETECT MALFUNCTIONING PART
BBIA0470E
Voltage: Battery voltage
PBIB2102E
BBIA0471E
Voltage: Battery voltage
JMBIA0604ZZ
Revision: March 2010 2008 QX56
Page 1644 of 4083
![INFINITI QX56 2008 Factory Service Manual P1572 ICC BRAKE SWITCHEC-345
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Check the following.
• Harness connectors M31, E152
• Fuse block (J/B) connector M60
• 10A fuse
• INFINITI QX56 2008 Factory Service Manual P1572 ICC BRAKE SWITCHEC-345
< COMPONENT DIAGNOSIS > [VK56DE]
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Check the following.
• Harness connectors M31, E152
• Fuse block (J/B) connector M60
• 10A fuse
•](/manual-img/42/57030/w960_57030-1643.png)
P1572 ICC BRAKE SWITCHEC-345
< COMPONENT DIAGNOSIS > [VK56DE]
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Check the following.
• Harness connectors M31, E152
• Fuse block (J/B) 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.
10.CHECK INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check harness continuity between ECM terminal 101 and stop lamp switch terminal 4. Refer to Wiring Diagram.
4. Also check harness for short to ground and short to power.
5. Check harness continuity between ECM terminal 101 and ICC hold relay terminal 6. Refer to Wiring Diagram.
6. Also check harness for short to ground and short to power.
7. Disconnect ICC unit harness connector.
8. Check harness continuity between ECM terminal 101 and ICC unit terminal 38. Refer to Wiring Diagram.
9. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 12.
NG >> GO TO 11.
11 .DETECT MALFUNCTIONING PART
Check the following.
• Harness connectors E34, B40
• Harness for open or short between ICC unit and ECM
>> Repair open circuit or short to ground or short to power in harness or connectors.
12.CHECK STOP LAMP SWITCH
Refer to EC-346, "
Component Inspection".
OK or NG
OK >> GO TO 13.
NG >> Replace stop lamp switch.
13.CHECK ICC BRAKE HOLD RELAY
Refer to EC-346, "
Component Inspection".
OK >> GO TO 14.
NG >> Replace ICC brake hold relay.
14.CHECK INTERMITTENT INCIDENT
Refer to GI-35, "
How to Check Terminal" and GI-38, "Intermittent Incident".
>> INSPECTION END
Continuity should exist.
Continuity should exist.
Continuity should exist.
Revision: March 2010
2008 QX56
Page 1647 of 4083
![INFINITI QX56 2008 Factory Service Manual EC-348
< COMPONENT DIAGNOSIS >[VK56DE]
P1572 ASCD BRAKE SWITCH
5. Check 1st trip DTC.
6. If 1st trip DTC is detected, go to
EC-348, "
Diagnosis Procedure".
If 1st trip DTC is not detec ted, go to the INFINITI QX56 2008 Factory Service Manual EC-348
< COMPONENT DIAGNOSIS >[VK56DE]
P1572 ASCD BRAKE SWITCH
5. Check 1st trip DTC.
6. If 1st trip DTC is detected, go to
EC-348, "
Diagnosis Procedure".
If 1st trip DTC is not detec ted, go to the](/manual-img/42/57030/w960_57030-1646.png)
EC-348
< COMPONENT DIAGNOSIS >[VK56DE]
P1572 ASCD BRAKE SWITCH
5. Check 1st trip DTC.
6. If 1st trip DTC is detected, go to
EC-348, "
Diagnosis Procedure".
If 1st trip DTC is not detec ted, go to the following step.
7. Drive the vehicle for at least 5 consecutive seconds under the following condition.
8. Check 1st trip DTC.
9. If 1st trip DTC is detected, go to EC-348, "
Diagnosis Procedure".
WITH GST
Follow the procedure “WITH CONSULT-III” above.
Diagnosis ProcedureINFOID:0000000001528789
1.CHECK OVERALL FUNCTION-I
With CONSULT-III
1. Turn ignition switch ON.
2. Select “BRAKE SW1” in “DAT A MONITOR” mode with CONSULT-III.
3. Check “BRAKE SW1” indication under the following conditions.
Without CONSULT-III
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-III
Check “BRAKE SW2” indication in “DATA MONITOR” mode.
VHCL SPEED SE More than 30 km/h (19 MPH)
Selector lever Suitable position
VHCL SPEED SE More than 30 km/h (19 MPH)
Selector lever Suitable position
Driving location Depress the brake pedal for more than
five seconds so as not to come off from
the above-mentioned condition.
CONDITION
INDICATION
Brake pedal: Slightly depressed OFF
Brake pedal: Fully released ON
CONDITIONVOLTAGE
Brake pedal: Slightly depressed Approximately 0V
Brake pedal: Fully released Battery voltage
MBIB0061E
Revision: March 2010 2008 QX56
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![INFINITI QX56 2008 Factory Service Manual P1572 ASCD BRAKE SWITCHEC-349
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OK INFINITI QX56 2008 Factory Service Manual P1572 ASCD BRAKE SWITCHEC-349
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Check voltage between ECM terminal 101 and ground under the following conditions.
OK](/manual-img/42/57030/w960_57030-1647.png)
P1572 ASCD BRAKE SWITCHEC-349
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Without CONSULT-III
Check voltage between ECM terminal 101 and ground under the following conditions.
OK or NG
OK >> GO TO 11.
NG >> GO TO 7.
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 voltage between ASCD brake switch terminal 1 and ground with CONSULT-III or tester.
OK or NG
OK >> GO TO 5.
NG >> GO TO 4.
4.DETECT MALFUNCTIONING PART
Check the following.
• Harness connectors M31, E152
• Fuse block (J/B) connector M4
• 10A fuse
• Harness for open or short between ASCD brake switch and fuse
>> Repair open circuit or short to ground or short to power in harness or connectors.
CONDITION INDICATION
Brake pedal: Fully released OFF
Brake pedal: Slightly depressed ON
CONDITIONVOLTAGE
Brake pedal: Fully released Approximately 0V
Brake pedal: Slightly depressed Battery voltage
PBIB1537E
BBIA0373E
Voltage: Battery voltage
PBIB0857E
Revision: March 2010 2008 QX56
Page 1649 of 4083
![INFINITI QX56 2008 Factory Service Manual EC-350
< COMPONENT DIAGNOSIS >[VK56DE]
P1572 ASCD BRAKE SWITCH
5.CHECK ASCD BRAKE SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Ch INFINITI QX56 2008 Factory Service Manual EC-350
< COMPONENT DIAGNOSIS >[VK56DE]
P1572 ASCD BRAKE SWITCH
5.CHECK ASCD BRAKE SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Ch](/manual-img/42/57030/w960_57030-1648.png)
EC-350
< COMPONENT DIAGNOSIS >[VK56DE]
P1572 ASCD BRAKE SWITCH
5.CHECK ASCD BRAKE SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check harness continuity between ECM terminal 108 and ASCD brake switch terminal 2. Refer to Wiring Diagram.
4. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 6.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
6.CHECK ASCD BRAKE SWITCH
Refer to EC-351, "
Component Inspection".
OK or NG
OK >> GO TO 11.
NG >> Replace ASCD brake switch.
7.CHECK STOP LAMP SWIT CH POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect stop lamp switch harness connector.
3. Check voltage between stop lamp switch terminal 3 and ground with CONSULT-III or tester.
OK or NG
OK >> GO TO 9.
NG >> GO TO 8.
8.DETECT MALFUNCTIONING PART
Check the following.
• Harness connectors M31, E152
• Fuse block (J/B) 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.
9.CHECK STOP LAMP SWITCH INPUT SIGNAL 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.Continuity should exist.
BBIA0373E
Voltage: Battery voltage
PBIB2102E
Revision: March 2010
2008 QX56
Page 1656 of 4083
![INFINITI QX56 2008 Factory Service Manual P1805 BRAKE SWITCHEC-357
< COMPONENT DIAGNOSIS > [VK56DE]
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1. Disconnect stop lamp switch harness connector.
2. Check voltage between stop lamp switch terminal 3 and gro INFINITI QX56 2008 Factory Service Manual P1805 BRAKE SWITCHEC-357
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1. Disconnect stop lamp switch harness connector.
2. Check voltage between stop lamp switch terminal 3 and gro](/manual-img/42/57030/w960_57030-1655.png)
P1805 BRAKE SWITCHEC-357
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1. Disconnect stop lamp switch harness connector.
2. Check voltage between stop lamp switch terminal 3 and ground
with CONSULT-III or tester.
OK or NG
OK >> GO TO 4.
NG >> GO TO 3.
3.DETECT MALFUNCTIONING PART
Check the following.
• Harness connectors M31, E152
• Fuse block (J/B) connector M60
• 10A fuse
• Harness for open and short between stop lamp switch and battery
>> Repair open circuit or short to ground or short to power in harness or connectors.
4.CHECK STOP LAMP SWITCH INPUT SI GNAL CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check harness continuity between ECM terminal 101 and stop lamp switch terminal 4. 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 STOP LAMP SWITCH
Refer to EC-358, "
Component Inspection".
OK or NG
OK >> GO TO 6.
NG >> Replace stop lamp switch.
6.CHECK INTERMITTENT INCIDENT
Refer to GI-35, "
How to Check Terminal" and GI-38, "Intermittent Incident".
>> INSPECTION END
BBIA0373E
Voltage: Battery voltage
PBIB2102E
Continuity should exist.
Revision: March 2010 2008 QX56