Nissan Frontier. Instruction - part 455

P1572 ASCD BRAKE SWITCH

EC-391

< DTC/CIRCUIT DIAGNOSIS >

[QR25DE]

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3. Check voltage between stop lamp switch terminal 1 and ground

with CONSULT or tester.

OK or NG

OK

>> GO TO 9.

NG

>> GO TO 8.

8.

DETECT MALFUNCTIONING PART

Check the following.

• Fuse block (J/B) connector E160

• 10A fuse (No.20)

• Harness for open or short between stop lamp switch and battery

>> Repair open circuit, 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 106 and stop lamp 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 10.

NG

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

10.

CHECK STOP LAMP SWITCH

Refer to 

EC-395, "Component Inspection"

.

OK or NG

OK

>> GO TO 11.

NG

>> Replace stop lamp switch. Refer to 

BR-20, "Exploded View"

.

11.

CHECK INTERMITTENT INCIDENT

Refer to 

GI-42, "Intermittent Incident"

.

>> INSPECTION END

M/T MODELS

1.

CHECK OVERALL FUNCTION-I

 With CONSULT

1. Turn ignition switch ON.

2. Select “BRAKE SW1” in “DATA MONITOR” mode with CONSULT.

3. Check “BRAKE SW1” indication under the following conditions.

 Without CONSULT

1. Turn ignition switch ON.

2. Check voltage between ECM terminal 110 and ground under the following conditions.

Voltage: Battery voltage

PBIB1184E

Continuity should exist.

CONDITION

INDICATION

Brake pedal and/or clutch pedal: Slightly depressed

OFF

Brake pedal and clutch pedal: Fully released

ON

EC-392

< DTC/CIRCUIT DIAGNOSIS >

[QR25DE]

P1572 ASCD BRAKE SWITCH

OK or NG

OK

>> GO TO 2.

NG 

>> GO TO 3.

2.

CHECK OVERALL FUNCTION-II

 With CONSULT

Check “BRAKE SW2” indication in “DATA MONITOR” mode. 

 Without CONSULT

Check voltage between ECM terminal 106 and ground under the following conditions.

OK or NG

OK

>> GO TO 14.

NG

>> GO TO 10.

3.

CHECK BRAKE PEDAL POSITION SWITCH CIRCUIT

1. Turn ignition switch OFF.

2. Disconnect clutch pedal position switch harness connector.

3. Turn ignition switch ON.

4. Check voltage between clutch pedal position switch terminal 1

and ground under the following conditions with CONSULT or

tester.

OK or NG

OK 

>> GO TO 8.

NG

>> GO TO 4.

4.

CHECK BRAKE PEDAL POSITION SWITCH POWER SUPPLY CIRCUIT

1. Turn ignition switch OFF.

2. Disconnect brake pedal position switch harness connector.

3. Turn ignition switch ON.

CONDITION

VOLTAGE

Brake pedal and/or clutch pedal: Slightly depressed

Approximately 0V

Brake pedal and clutch pedal: Fully released

Battery voltage

CONDITION

INDICATION

Brake pedal: Fully released

OFF

Brake pedal: Slightly depressed

ON

CONDITION

VOLTAGE

Brake pedal: Fully released

Approximately 0V

Brake pedal: Slightly depressed

Battery voltage

CONDITION

VOLTAGE

Brake pedal: Fully released

Battery voltage

Brake pedal: Slightly depressed

Approx. 0V

PBIB0799E

P1572 ASCD BRAKE SWITCH

EC-393

< DTC/CIRCUIT DIAGNOSIS >

[QR25DE]

C

D

E

F

G

H

I

J

K

L

M

A

EC

N

P

O

4. Check voltage between brake pedal position switch terminal 1

and ground with CONSULT or tester.

OK or NG

OK

>> GO TO 6.

NG

>> GO TO 5.

5.

DETECT MALFUNCTIONING PART

Check the following.

• Fuse block (J/B) connector E160

• 10A fuse (No.12)

• Harness for open or short between brake pedal position switch and fuse

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

6.

CHECK BRAKE PEDAL POSITION SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT

1. Turn ignition switch OFF.

2. Check harness continuity between brake pedal position switch terminal 2 and clutch pedal position switch

terminal 1. 

Refer to Wiring Diagram.

3. Also check harness for short to ground and short to power.
OK or NG

OK

>> GO TO 7.

NG

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

7.

CHECK BRAKE PEDAL POSITION SWITCH

Refer to 

EC-395, "Component Inspection"

.

OK or NG

OK

>> GO TO 14.

NG

>> Replace brake pedal position switch. Refer to 

BR-20, "Exploded View"

.

8.

CHECK CLUTCH PEDAL POSITION 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 110 and clutch pedal position 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 9.

NG

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

9.

CHECK CLUTCH PEDAL POSITION SWITCH

Refer to 

EC-395, "Component Inspection"

.

OK or NG

OK

>> GO TO 14.

NG

>> Replace clutch pedal position switch. Refer to 

CL-9, "Exploded View"

.

10.

CHECK STOP LAMP SWITCH POWER SUPPLY CIRCUIT

Voltage: Battery voltage

PBIB0857E

Continuity should exist.

Continuity should exist.

EC-394

< DTC/CIRCUIT DIAGNOSIS >

[QR25DE]

P1572 ASCD BRAKE SWITCH

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 or tester.

OK or NG

OK

>> GO TO 12.

NG

>> GO TO 11.

11.

DETECT MALFUNCTIONING PART

Check the following.

• Fuse block (J/B) connector E160

• 10A fuse(No.20)

• Harness for open or short between stop lamp switch and fuse

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

12.

CHECK STOP LAMP SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT

1. Disconnect ECM harness connector.

2. Check harness continuity between ECM terminal 106 and stop lamp 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 13.

NG

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

13.

CHECK STOP LAMP SWITCH

Refer to 

EC-395, "Component Inspection"

.

OK or NG

OK

>> GO TO 14.

NG

>> Replace stop lamp switch. Refer to 

BR-20, "Exploded View"

.

14.

CHECK INTERMITTENT INCIDENT

Refer to 

GI-42, "Intermittent Incident"

.

>> INSPECTION END

BBIA0560E

Voltage: Battery voltage

PBIB0117E

Continuity should exist.