Nissan Quest E52. Manual - part 539

EC-366

< DTC/CIRCUIT DIAGNOSIS >

[VQ35DE]

P1572 ASCD BRAKE SWITCH

5.

Check 1st trip DTC.

Is 1st trip DTC detected?

YES

>> Go to 

EC-367, "Diagnosis Procedure"

.

NO

>> GO TO 4.

4.

PERFORM DTC CONFIRMATION PROCEDURE A-II

1.

Drive the vehicle for at least 5 consecutive seconds under the following conditions.

CAUTION:

Always drive vehicle at a safe speed.
NOTE:
This procedure may be conducted with the drive wheels lifted in the shop or by driving the vehicle.
If a road test is expected to be easier, it is unnecessary to lift the vehicle.

2.

Check 1st trip DTC.

Is 1st trip DTC detected?

YES

>> Go to 

EC-367, "Diagnosis Procedure"

.

NO

>> INSPECTION END

5.

PERFORM COMPONENT FUNCTION CHECK

Perform component function check. Refer to 

EC-366, "Component Function Check"

.

NOTE:
Use component function check to check the overall function of ASCD brake switch. During this check, a DTC
might not be confirmed.

Is the inspection result normal?

YES

>> INSPECTION END

NO

>> Go to 

EC-367, "Diagnosis Procedure"

.

Component Function Check

INFOID:0000000009651215

1.

PERFORM COMPONENT FUNCTION CHECK

1.

Turn ignition switch ON.

2.

Check the voltage between ECM harness connectors.

Is the inspection result normal?

YES

>> INSPECTION END

NO

>> GO TO 2.

2.

PERFORM COMPONENT FUNCTION CHECK-II

Check the voltage between ECM harness connectors.

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.

ECM

Condition

Voltage

Con-

nector

+

–

Terminal

Terminal

E16

126

(ASCD 

brake 

switch 

signal)

128

Brake pedal

Slightly 
depressed

Approx. 0 V

Fully re-
leased

Battery voltage

P1572 ASCD BRAKE SWITCH

EC-367

< DTC/CIRCUIT DIAGNOSIS >

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Is the inspection result normal?

YES

>> INSPECTION END

NO

>> Go to 

EC-367, "Diagnosis Procedure"

.

Diagnosis Procedure

INFOID:0000000009651216

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 the voltage between ECM harness connectors.

Is the inspection result normal?

YES

>> GO TO 2.

NO

>> GO TO 3.

2.

CHECK OVERALL FUNCTION-II

 With CONSULT

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

 Without CONSULT

Check the voltage between ECM harness connectors.

ECM

Condition

Voltage

Con-

nector

+

–

Terminal

Terminal

E16

122

(Stop 

lamp 

switch 

signal)

128

Brake pedal

Slightly 
depressed

Battery voltage

Fully re-
leased

Approx. 0 V

Monitor item

Condition

Indication

BRAKE SW1

Brake pedal

Slightly depressed

OFF

Fully released

ON

ECM

Condition

Voltage

Con-

nector

+

–

Terminal

Terminal

E16

126

(ASCD 

brake 

switch 

signal)

128

Brake pedal

Slightly 
depressed

Approx. 0 V

Fully re-
leased

Battery voltage

Monitor item

Condition

Indication

BRAKE SW2

Brake pedal

Slightly depressed

ON

Fully released

OFF

EC-368

< DTC/CIRCUIT DIAGNOSIS >

[VQ35DE]

P1572 ASCD BRAKE SWITCH

Is the inspection result normal?

YES

>> GO TO 16.

NO

>> 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 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.
• Fuse block (J/B) connector E103
• 10 A fuse (No. 3)
• Harness for open or short between ASCD brake switch and fuse

>> Repair open circuit, short to ground or short to power 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 switch 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 6.

NO

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

6.

CHECK ASCD BRAKE SWITCH

Refer to 

EC-370, "Component Inspection (ASCD Brake Switch)"

.

Is the inspection result normal?

YES

>> GO TO 9.

NO

>> Replace ASCD brake switch. Refer to 

BR-18, "Exploded View"

.

7.

CHECK STOP LAMP SWITCH POWER SUPPLY CIRCUIT

1.

Turn ignition switch OFF.

ECM

Condition

Voltage

Con-

nector

+

–

Terminal

Terminal

E16

122

(Stop 

lamp 

switch 

signal)

128

Brake pedal

Slightly 
depressed

Battery voltage

Fully re-
leased

Approx. 0 V

ASCD brake switch

Ground

Voltage

Connector

Terminal

E109

1

Ground

Battery voltage

ASCD brake switch

ECM

Continuity

Connector

Terminal

Connector

Terminal

E109

2

E16

126

Existed

P1572 ASCD BRAKE SWITCH

EC-369

< DTC/CIRCUIT DIAGNOSIS >

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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 9.

NO

>> GO TO 8.

8.

DETECT MALFUNCTIONING PART

Check the following.
• Fuse block (J/B) connector E103
• 10 A fuse (No. 7)
• 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 RELAY GROUND CIRCUIT

1.

Turn ignition switch OFF.

2.

Disconnect stop lamp relay harness connector.

3.

Check the continuity between stop lamp relay harness connector and ground.

Is the inspection result normal?

YES

>> GO TO 10.

NO

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

10.

CHECK STOP LAMP SWITCH INPUT SIGNAL CIRCUIT

1.

Connect stop lamp switch harness connector.

2.

Turn ignition switch ON.

3.

Check the voltage between stop lamp relay harness connector and ground.

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 stop lamp switch and stop lamp relay

Is the inspection result normal?

YES

>> GO TO 14.

NO

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

12.

CHECK STOP LAMP RELAY POWER SUPPLY CIRCUIT

1.

Check the voltage between stop lamp relay harness connector and ground.

Stop lamp switch

Ground

Voltage

Connector

Terminal

E115

1

Ground

Battery voltage

Stop lamp relay

Ground

Continuity

Connector

Terminal

E15

1

Ground

Existed

Stop lamp relay

Ground

Condition

Voltage (V)

Connector

Terminal

E15

2

Ground

Brake 
pedal

Slightly de-
pressed

Battery voltage

Fully released

Approx. 0