P1572 ASCD BRAKE SWITCH

VR38

P1572

Description
DTC Logic
Diagnosis Procedure
Component Inspection (ASCD Brake Switch)
Component Inspection (Stop Lamp Switch)

Description

When the brake pedal is depressed, ASCD brake 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 System Description (GT-R certified NISSAN dealer) for the ASCD function.

DTC Logic

DTC DETECTION LOGIC

NOTE：

If DTC P1572 is displayed with DTC P0605, first perform the trouble diagnosis for DTC P0605. Refer to DTC Logic (GT-R certified NISSAN dealer).
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 in turned OFF. And even when malfunction A is detected in two consecutive trips, DTC is not stored in ECM memory.

DTC No.	Trouble diagnosis name	DTC detecting condition		Possible cause
P1572	ASCD brake switch	A)	When the vehicle speed is above 30 km/h (19 MPH), ON signals from the stop lamp switch and the ASCD brake switch are sent to the ECM at the same time.	Harness or connectors (The stop lamp switch circuit is shorted.) Harness or connectors (The ASCD brake switch circuit is shorted.) Stop lamp switch ASCD brake switch Incorrect stop lamp switch installation Incorrect ASCD brake switch installation ECM
		B)	ASCD brake switch signal is not sent to ECM for extremely long time while the vehicle is being drived.

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING

2.PERFORM DTC CONFIRMATION PROCEDURE FOR MALFUNCTION A

3.PERFORM DTC CONFIRMATION PROCEDURE

Diagnosis Procedure

1.CHECK OVERALL FUNCTION-I

2.CHECK OVERALL FUNCTION-II

3.CHECK ASCD BRAKE SWITCH POWER SUPPLY CIRCUIT

4.DETECT MALFUNCTIONING PART

5.CHECK ASCD BRAKE SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT

6.DETECT MALFUNCTIONING PART

7.CHECK ASCD BRAKE SWITCH

8.CHECK STOP LAMP SWITCH POWER SUPPLY CIRCUIT

9.DETECT MALFUNCTIONING PART

10.CHECK STOP LAMP SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT

11.DETECT MALFUNCTIONING PART

12.CHECK STOP LAMP SWITCH

13.CHECK INTERMITTENT INCIDENT

Component Inspection (ASCD Brake Switch)

1.CHECK ASCD BRAKE SWITCH-I

2.CHECK ASCD BRAKE SWITCH-II

Component Inspection (Stop Lamp Switch)

1.CHECK STOP LAMP SWITCH-I

2.CHECK STOP LAMP SWITCH-II

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.

Monitor item	Condition		Indication
BRAKE SW1	Brake pedal	Slightly depressed	OFF
		Fully released	ON

ECM			Condition		Voltage (V)
Connector	+	–
	Terminal	Terminal
M107	117 (ASCD brake switch signal)	128	Brake pedal	Slightly depressed	Approx. 0
				Fully released	Battery voltage

Monitor item	Condition		Indication
BRAKE SW2	Brake pedal	Slightly depressed	ON
		Fully released	OFF

ASCD brake switch		Ground	Voltage
Connector	Terminal
E109	1	Ground	Battery voltage

ASCD brake switch		ECM		Continuity
Connector	Terminal	Connector	Terminal	Continuity
E109	2	M107	117	Existed

Stop lamp switch		Ground	Voltage
Connector	Terminal
E110	1	Ground	Battery voltage

Terminals	Condition		Continuity
1 and 2	Brake pedal	Fully released	Existed
		Slightly depressed	Not existed