Infiniti FX35 / FX45. Manual - part 427

DTC P1572 ICC BRAKE SWITCH

EC-469

< SERVICE INFORMATION >

[VQ35DE]

C

D

E

F

G

H

I

J

K

L

M

A

EC

N

P

O

Check voltage between ECM terminal 101 and ground under the fol-
lowing conditions.

OK or NG

OK

>> GO TO 17.

NG

>> GO TO 12.

3.

CHECK DTC WITH ICC UNIT

Refer to 

ACS-35

.

OK or NG

OK

>> GO TO 4.

NG

>> Repair or replace.

4.

CHECK ICC BRAKE SWITCH 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 3 and
ground with CONSULT-III or tester.

OK or NG

OK 

>> GO TO 9.

NG

>> GO TO 5.

5.

CHECK ICC BRAKE SWITCH POWER SUPPLY CIRCUIT

1.

Turn ignition switch OFF.

CONDITION

VOLTAGE

Brake pedal: Fully released

Approximately 0V

Brake pedal: Slightly depressed

Battery voltage

PBIB1537E

PBIB1531E

Voltage: Battery voltage

PBIB1538E

EC-470

< SERVICE INFORMATION >

[VQ35DE]

DTC P1572 ICC BRAKE SWITCH

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-III or tester.

OK or NG

OK

>> GO TO 7.

NG

>> GO TO 6.

6.

DETECT MALFUNCTIONING PART

Check the following.
• Fuse block (J/B) connector E201
• 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.

7.

CHECK ICC BRAKE SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT-I

1.

Turn ignition switch OFF.

2.

Check harness continuity between ICC brake hold relay terminal 3 and ICC brake switch terminal 2. 
Refer to 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 SWITCH

Refer to 

EC-472, "Component Inspection"

.

OK or NG

OK

>> GO TO 17.

NG

>> Replace ICC brake switch.

9.

CHECK ICC BRAKE SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT-II

1.

Turn ignition switch OFF.

2.

Disconnect ECM harness connector.

3.

Check harness continuity between ICC brake hold relay terminal 4 and ECM terminal 108.
Refer Wiring Diagram.

4.

Also check harness for short to ground and short to power.

PBIB1539E

Voltage: Battery voltage

PBIB0857E

Continuity should exist.

Continuity should exist.

DTC P1572 ICC BRAKE SWITCH

EC-471

< SERVICE INFORMATION >

[VQ35DE]

C

D

E

F

G

H

I

J

K

L

M

A

EC

N

P

O

OK or NG

OK

>> GO TO 11.

NG

>> GO TO 10.

10.

DETECT MALFUNCTIONING PART

Check the following.
• Harness connectors E211, M41
• Harness for open or short between ICC brake hold relay and ECM

>> Repair open circuit or short to ground or short to power in harness or connectors.

11.

CHECK ICC BRAKE HOLD RELAY

Refer to 

EC-472, "Component Inspection"

.

OK

>> GO TO 17.

NG

>> Replace ICC brake hold relay.

12.

CHECK STOP LAMP SWITCH POWER SUPPLY CIRCUIT

1.

Turn ignition switch OFF.

2.

Disconnect stop lamp switch harness connector.

3.

Check voltage between stop lamp switch terminal 1 and ground
with CONSULT -II or tester.

OK or NG

OK

>> GO TO 14.

NG

>> GO TO 13.

13.

DETECT MALFUNCTIONING PART

Check the following.
• Fuse block (J/B) connector E201
• 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.

14.

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 2.
Refer to Wiring Diagram.

3.

Also check harness for short to ground and short to power.

PBIB1539E

Voltage: Battery voltage

PBIB1184E

Continuity should exist.

EC-472

< SERVICE INFORMATION >

[VQ35DE]

DTC P1572 ICC BRAKE SWITCH

OK or NG

OK

>> GO TO 16.

NG

>> GO TO 15.

15.

DETECT MALFUNCTIONING PART

Check the following.
• Harness connectors E211, M41
• Harness for open or short between ECM and stop lamp switch

>> Repair open circuit or short to ground or short to power in harness or connectors.

16.

CHECK STOP LAMP SWITCH

Refer to 

EC-472, "Component Inspection"

 

OK or NG

OK

>> GO TO 17.

NG

>> Replace stop lamp switch.

17.

CHECK INTERMITTENT INCIDENT

Refer to 

EC-139

.

>> INSPECTION END

Component Inspection

INFOID:0000000001326336

ICC BRAKE SWITCH

1.

Turn ignition switch OFF.

2.

Disconnect ICC brake switch harness connector.

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-5

, 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 1 and 2
under the following conditions.

If NG, adjust stop lamp switch installation, refer to 

BR-5

, and

perform step 3 again.

ICC BRAKE HOLD RELAY

1.

Apply 12V direct current between ICC brake hold relay terminals 1 and 2.

Condition

Continuity

Brake pedal: Fully released

Should exist

Brake pedal: Slightly depressed

Should not exist

SEC023D

Condition

Continuity

Brake pedal: Fully released

Should not exist

Brake pedal: Slightly depressed

Should exist

PBIB1185E