Nissan X-Trail 32. Instruction — part 805

P1572 ASCD BRAKE SWITCH

EC-349

< DTC/CIRCUIT DIAGNOSIS >

[MR20DD]

C

D

E

F

G

H

I

J

K

L

M

A

EC

N

P

O

Is the inspection result normal?

YES

>> INSPECTION END

NO

>> GO TO 7.

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.

4.

Check the voltage between brake pedal position switch harness connector and ground.

Is the inspection result normal?

YES

>> GO TO 5.

NO

>> Perform the trouble diagnosis for power supply circuit.

5.

CHECK BRAKE PEDAL POSITION SWITCH INPUT SIGNAL CIRCUIT

1.

Disconnect ECM harness connector.

2.

Check the continuity between brake pedal position switch harness connector and ECM harness connec-
tor.

3.

Also check harness for short to ground and to power.

Is the inspection result normal?

YES

>> GO TO 6.

NO

>> Repair or replace malfunctioning part.

6.

CHECK BRAKE PEDAL POSITION SWITCH

Check the brake pedal position switch. Refer to

EC-350, "Component Inspection (Brake Pedal Position

Switch)"

.

Is the inspection result normal?

YES

>> INSPECTION END

NO

>> Replace brake pedal position switch. Refer to

BR-21, "Removal and Installation"

.

7.

CHECK STOP LAMP SWITCH POWER SUPPLY CIRCUIT

1.

Turn ignition switch OFF.

2.

Disconnect stop lamp switch harness connector.

3.

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

E16

115

128

Brake pedal

Slightly de-
pressed

Battery voltage

Fully released

0 V

+

−

Voltage

Brake pedal position switch

Connector

Terminal

CVT models

E124

1

Ground

Battery voltage

M/T models

E119

1

Ground

Battery voltage

+

−

Continuity

Brake pedal position switch

ECM

Connector

Terminal

Connector

Terminal

CVT models

E124

2

E16

116

Existed

M/T models

E119

2

E16

116

Existed

EC-350

< DTC/CIRCUIT DIAGNOSIS >

[MR20DD]

P1572 ASCD BRAKE SWITCH

Is the inspection result normal?

YES

>> GO TO 8.

NO

>> Perform the trouble diagnosis for power supply circuit.

8.

CHECK STOP LAMP SWITCH SIGNAL CIRCUIT

1.

Disconnect ECM harness connector.

2.

Check the continuity between stop lamp switch harness connector and ECM harness connector.

3.

Also check harness for short to ground and to power.

Is the inspection result normal?

YES

>> GO TO 9.

NO

>> Repair or replace malfunctioning part.

9.

CHECK STOP LAMP SWITCH

Check the stop lamp switch. Refer to

EC-351, "Component Inspection (Stop Lamp Switch)"

.

Is the inspection result normal?

YES

>> INSPECTION END

NO

>> Replace stop lamp switch. Refer to

BR-21, "Exploded View"

.

Component Inspection (Brake Pedal Position Switch)

INFOID:0000000010775246

1.

CHECK BRAKE PEDAL POSITION SWITCH-1

1.

Turn ignition switch OFF.

2.

Disconnect brake pedal position harness connector.

3.

Check the continuity between brake pedal position switch terminals as per the following conditions.

Is the inspection result normal?

YES

>> INSPECTION END

NO

>> GO TO 2.

2.

CHECK BRAKE PEDAL POSITION SWITCH-2

1.

Adjust brake pedal position switch installation. Refer to

BR-22, "Inspection and Adjustment"

.

2.

Check the continuity between brake pedal position switch terminals as per the following conditions.

+

−

Voltage

Stop lamp switch

Connector

Terminal

CVT models

E115

1

Ground

Battery volatage

M/T models

E120

1

+

−

Continuity

Stop lamp switch

ECM

Connector

Terminal

Connector

Terminal

CVT models

E115

2

E16

115

Existed

M/T models

E120

2

Terminals

Condition

Continuity

1 and 2

Brake pedal

Fully released

Existed

Slightly depressed

Not existed

P1572 ASCD BRAKE SWITCH

EC-351

< DTC/CIRCUIT DIAGNOSIS >

[MR20DD]

C

D

E

F

G

H

I

J

K

L

M

A

EC

N

P

O

Is the inspection result normal?

YES

>> INSPECTION END

NO

>> Replace brake pedal position switch. Refer to

BR-21, "Removal and Installation"

.

Component Inspection (Stop Lamp Switch)

INFOID:0000000010775247

1.

CHECK STOP LAMP SWITCH-1

1.

Turn ignition switch OFF.

2.

Disconnect stop lamp switch harness connector.

3.

Check the continuity between stop lamp switch terminals as per the following conditions.

Is the inspection result normal?

YES

>> INSPECTION END

NO

>> GO TO 2.

2.

CHECK STOP LAMP SWITCH-2

1.

Adjust stop lamp switch installation. Refer to

BR-22, "Inspection and Adjustment"

.

2.

Check the continuity between stop lamp switch terminals as per the following conditions.

Is the inspection result normal?

YES

>> INSPECTION END

NO

>> Replace stop lamp switch. Refer to

BR-21, "Removal and Installation"

.

Brake pedal position switch

Condition

Continuity

+

−

Terminal

1

2

Brake pedal

Fully released

Existed

Slightly depressed

Not existed

Stop lamp switch

Condition

Continuity

+

−

Terminal

1

2

Brake pedal

Fully released

Not existed

Slightly depressed

Existed

Stop lamp switch

Condition

Continuity

+

−

Terminal

1

2

Brake pedal

Fully released

Not existed

Slightly depressed

Existed

EC-352

< DTC/CIRCUIT DIAGNOSIS >

[MR20DD]

P1574 ASCD VEHICLE SPEED SENSOR

P1574 ASCD VEHICLE SPEED SENSOR

DTC Description

INFOID:0000000010775248

The ECM receives two vehicle speed sensor signals via CAN communication line. One is sent from combina-
tion meter, and the other is from CVT C/U. The ECM uses these signals for ASCD control. Refer to

EC-64,

"AUTOMATIC SPEED CONTROL DEVICE (ASCD) : System Description"

for ASCD functions.

DTC DETECTION LOGIC

POSSIBLE CAUSE

• Harness or connectors (CAN communication line is open or shorted.)
• Combination meter
• Wheel sensor
• ABS actuator and electric unit (control unit)
• ECM
• TCM

FAIL-SAFE

Not applicable

DTC CONFIRMATION PROCEDURE

1.

CHECK DTC PRIORITY

If DTC P1574 is displayed with DTC U1001, P0500, P0605 or P0607, first perform the trouble diagnosis for
DTC U1001, P0500, P0605 or P0607.
Is applicable DTC detected?

YES

>> Perform diagnosis of applicable. Refer to

EC-109, "DTC Index"

.

NO

>> GO TO 2.

2.

PRECONDITIONING

If DTC Confirmation Procedure has been previously conducted, always perform the following procedure
before conducting the next test.
1.

Turn ignition switch OFF and wait at least 10 seconds.

2.

Turn ignition switch ON.

3.

Turn ignition switch OFF and wait at least 10 seconds.

>> GO TO 3.

3.

PERFORM DTC CONFIRMATION PROCEDURE

1.

Start engine.

2.

Drive the vehicle at more than 40 km/h (25 MPH).

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.

3.

Check DTC.

Is DTC detected?

YES

>> Proceed to

EC-353, "Diagnosis Procedure"

.

NO-1

>> To check malfunction symptom before repair: Refer to

GI-44, "Intermittent Incident"

.

NO-2

>> Confirmation after repair: INSPECTION END

DTC No.

CONSULT screen terms

(Trouble diagnosis content)

DTC detecting condition

P1574

ASCD VHL SPD SEN
(ASCD vehicle speed sensor)

ECM detects a difference between two vehicle speed signals is out of the
specified range.