Nissan Frontier. Manual - part 454

P1564 ASCD STEERING SWITCH

EC-387

< DTC/CIRCUIT DIAGNOSIS >

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If NG, replace ASCD steering switch.

CANCEL switch

Pressed

Approx. 250

Released

Approx. 4,000

RESUME/ACCELERATE 
switch

Pressed

Approx. 1,480

Released

Approx. 4,000

SET SW/COAST switch

Pressed

Approx. 660

Released

Approx. 4,000

Switch

Condition

Resistance [

Ω]

EC-388

< DTC/CIRCUIT DIAGNOSIS >

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P1572 ASCD BRAKE SWITCH

P1572 ASCD BRAKE SWITCH

Component Description

INFOID:0000000009481083

When the brake pedal is depressed, brake pedal position switch is turned OFF and stop lamp switch is turned

ON. ECM detects the state of the brake pedal by those two types of input (ON/OFF signal).

Refer to 

CCS-3

 for the ASCD function.

On Board Diagnosis Logic

INFOID:0000000009481084

This self-diagnosis has the one trip detection logic.

The MIL will not light up for this self-diagnosis.

NOTE:

• If DTC P1572 is displayed with DTC P0605, first perform the trouble diagnosis for DTC P0605. Refer

to 

EC-347

.

• This self-diagnosis has the one trip detection logic. When malfunction A is detected, DTC is not

stored in ECM memory. And in that case, 1st trip DTC and 1st trip freeze frame data are displayed.

1st trip DTC is erased when ignition switch OFF. And even when malfunction A is detected in two

consecutive trips, DTC is not stored in ECM memory.

DTC Confirmation Procedure

INFOID:0000000009481085

CAUTION:

Always drive vehicle at a safe speed.

NOTE:

• If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at

least 10 seconds before conducting the next test.

• The procedure for malfunction B is not described. It takes an extremely long time to complete the procedure

for malfunction B. By performing the procedure for malfunction A, the condition that causes malfunction B

can be detected. 

TESTING CONDITION:

Steps 4 and 7 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.

 WITH CONSULT

1. Start engine.
2. Select “DATA MONITOR” mode with CONSULT.
3. Press MAIN switch and make sure that CRUISE indicator lights up.
4. Drive the vehicle for at least 5 consecutive seconds under the following condition.

DTC No.

Trouble diagnosis name

DTC Detecting Condition

Possible Cause

P1572
1572

ASCD brake switch

A)

• When the vehicle speed is above 

30km/h (19 MPH), ON signals from 
the stop lamp switch and the brake 
pedal position switch are sent to ECM 
at the same l time.

• Harness or connectors

(The stop lamp switch circuit is shorted.)

• Harness or connectors

(The brake pedal position switch circuit is 
shorted.)

• Harness or connectors

(The clutch pedal position switch circuit is 
shorted.) (M/T models)

• Stop lamp switch
• Brake pedal position switch
• Clutch pedal position switch (M/T models)
• Incorrect stop lamp switch installation
• Incorrect brake pedal position switch instal-

lation

• Incorrect clutch pedal position switch instal-

lation (M/T models)

• ECM

B)

• Brake pedal position switch signal is 

not sent to ECM for extremely long 
time while the vehicle is driving

VHCL SPEED SE

More than 30 km/h (19 MPH)

Shift lever

Suitable position 

P1572 ASCD BRAKE SWITCH

EC-389

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5. Check DTC.
6. If DTC is detected, go to 

EC-389, "Diagnosis Procedure"

.

If DTC is not detected, go to the following steps.

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

8. Check DTC.
9. If DTC is detected, go to 

EC-389, "Diagnosis Procedure"

.

 WITH GST

Follow the procedure “WITH CONSULT” above.

Diagnosis Procedure

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A/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.

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.

VHCL SPEED SE

More than 30 km/h (19 MPH)

Shift lever

Suitable position 

Driving location

Depress the brake pedal for more than 5 
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

CONDITION

VOLTAGE

Brake pedal: Slightly depressed

Approximately 0V

Brake pedal: Fully released

Battery voltage

CONDITION

INDICATION

Brake pedal: Fully released

OFF

Brake pedal: Slightly depressed

ON

EC-390

< DTC/CIRCUIT DIAGNOSIS >

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P1572 ASCD BRAKE SWITCH

OK or NG

OK

>> GO TO 11.

NG

>> GO TO 7.

3.

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 voltage between brake pedal position switch terminal 1

and ground with CONSULT or tester.

OK or NG

OK

>> GO TO 5.

NG

>> GO TO 4.

4.

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 or short to ground in harness or connectors.

5.

CHECK BRAKE 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 brake 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 6.

NG

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

6.

CHECK BRAKE PEDAL POSITION SWITCH

Refer to 

EC-395, "Component Inspection"

.

OK or NG

OK

>> GO TO 11.

NG

>> Replace brake pedal position switch. Refer to 

BR-20, "Exploded View"

.

7.

CHECK STOP LAMP SWITCH POWER SUPPLY CIRCUIT

1. Turn ignition switch OFF.

2. Disconnect stop lamp switch harness connector.

CONDITION

VOLTAGE

Brake pedal: Fully released

Approximately 0V

Brake pedal: Slightly depressed

Battery voltage

Voltage: Battery voltage

PBIB0857E

Continuity should exist.