Page 1645 of 2896

EC-476Revision: June 2006
DTC P1572 ASCD BRAKE SWITCH
2007 Versa
Specification data are reference values and are measured between each terminal and ground.
CAUTION:
Do not use ECM ground terminals when measuring input/output voltage. Doing so may result in dam-
age to the ECM's transistor. Use a ground other than ECM terminals, such as the ground.
Diagnostic ProcedureUBS00QLR
1. CHECK OVERALL FUNCTION-I
With CONSULT-II
1. Turn ignition switch ON.
2. Select “BRAKE SW1” in “DATA MONITOR” mode with CON-
SULT-II.
3. Check “BRAKE SW1” indication under the following conditions.
M/T models
A/T and CVT models
Without CONSULT-II
1. Turn ignition switch ON.
2. Check voltage between ECM terminal 100 and ground under the
following conditions.
M/T models
A/T and CVT models
OK or NG
OK >> GO TO 2.
NG (M/T models) >>GO TO 3.
NG (A/T and CVT models) >>GO TO 4.
TERMI-
NAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
99 R Stop lamp switch[Ignition switch: ON]
Brake pedal: Fully releasedApproximately 0V
[Ignition switch: ON]
Brake pedal: Slightly depressedBATTERY VOLTAGE
(11 - 14V)
100 G ASCD brake switch
Brake pedal: Slightly depressed (A/T, CVT)
Brake pedal and clutch pedal: Fully released
(M/T) Approximately 0V
Brake pedal: Slightly depressed (A/T, CVT)
Brake pedal and/or clutch pedal: Slightly
depressed (M/T)BATTERY VOLTAGE
(11 - 14V)
CONDITION INDICATION
Clutch pedal and/or brake pedal: Slightly depressed OFF
Clutch pedal and brake pedal: Fully released ON
CONDITION INDICATION
Brake pedal: Slightly depressed OFF
Brake pedal: Fully released ON
CONDITION VOLTAGE
Clutch pedal and/or brake pedal: Slightly depressed Approximately 0V
Clutch pedal and brake pedal: Fully released Battery voltage
CONDITION VOLTAGE
Brake pedal: Slightly depressed Approximately 0V
Brake pedal: Fully released Battery voltage
SEC0 11D
PBIB3315E
Page 1646 of 2896
DTC P1572 ASCD BRAKE SWITCH
EC-477
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EC
Revision: June 20062007 Versa
2. CHECK OVERALL FUNCTION-II
With CONSULT-II
Check “BRAKE SW2” indication in “DATA MONITOR” mode.
Without CONSULT-II
Check voltage between ECM terminal 99 and ground under the fol-
lowing conditions.
OK or NG
OK >> GO TO 15.
NG >> GO TO 11.
3. CHECK ASCD CLUTCH SWITCH POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect ASCD clutch switch (1) harness connector.
–Clutch pedal (2)
3. Turn ignition switch ON.
4. Check voltage between ASCD clutch switch terminal 1 and
ground with CONSULT-II or tester.
OK or NG
OK >> GO TO 9.
NG >> GO TO 4.
CONDITION INDICATION
Brake pedal: Fully released OFF
Brake pedal: Slightly depressed ON
SEC0 13 D
CONDITION VOLTAGE
Brake pedal: Fully released Approximately 0V
Brake pedal: Slightly depressed Battery voltage
PBIB0 311 E
BBIA0709E
Voltage: Battery voltage
PBIB0857E
Page 1647 of 2896

EC-478Revision: June 2006
DTC P1572 ASCD BRAKE SWITCH
2007 Versa
4. CHECK ASCD BRAKE SWITCH POWER SUPPLY
1. Turn ignition switch OFF.
2. Disconnect ASCD brake switch (2) harness connector.
–Stop lamp switch (1)
3. Turn ignition switch ON.
4. Check voltage between ASCD brake switch terminal 1 and
ground under the following conditions with CONSULT-II or
tester.
OK or NG
OK (M/T models) >>GO TO 6.
OK (A/T and CVT models) >>GO TO 7.
NG >> GO TO 5.
5. DETECT MALFUNCTIONING PART
Check the following.
Harness connectors M69, E7
10A fuse
Harness for open or short between ASCD brake switch and fuse
>> Repair open circuit or short to ground or short to power in harness or connectors.
6. CHECK ASCD CLUTCH SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Check harness continuity between ASCD brake switch terminal 2 and ASCD clutch 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 8.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
BBIA0708E
CONDITION VOLTAGE
Clutch pedal: Fully released Battery voltage
Clutch pedal: Slightly depressed Approx. 0V
PBIB0857E
Continuity should exist.
Page 1648 of 2896

DTC P1572 ASCD BRAKE SWITCH
EC-479
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EC
Revision: June 20062007 Versa
7. CHECK ASCD BRAKE 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 100 and ASCD brake 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 8.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
8. CHECK ASCD BRAKE SWITCH
Refer to EC-481, "
Component Inspection" .
OK or NG
OK >> GO TO 15.
NG >> Replace ASCD brake switch.
9. CHECK ASCD CLUTCH 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 100 and ASCD clutch 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 10.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
10. CHECK ASCD CLUTCH SWITCH
Refer to EC-481, "
Component Inspection"
OK or NG
OK >> GO TO 15.
NG >> Replace ASCD clutch switch.Continuity should exist.
Continuity should exist.
Page 1650 of 2896

DTC P1572 ASCD BRAKE SWITCH
EC-481
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Revision: June 20062007 Versa
14. CHECK STOP LAMP SWITCH
Refer to EC-481, "
Component Inspection"
OK or NG
OK >> GO TO 15.
NG >> Replace stop lamp switch.
15. CHECK INTERMITTENT INCIDENT
Refer to EC-143, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
>>INSPECTION END
Component InspectionUBS00QLS
ASCD BRAKE SWITCH
1. Turn ignition switch OFF.
2. Disconnect ASCD brake switch harness connector.
3. Check continuity between ASCD brake switch terminals 1 and 2
under the following conditions.
If NG, adjust ASCD brake switch installation, refer to BR-6,
"BRAKE PEDAL" , and perform step 3 again.
ASCD CLUTCH SWITCH
1. Turn ignition switch OFF.
2. Disconnect ASCD clutch switch harness connector.
3. Check continuity between ASCD clutch switch terminals 1 and 2
under the following conditions.
If NG, adjust ASCD clutch switch installation, refer to CL-5,
"CLUTCH PEDAL" , and perform step 3 again.
Condition Continuity
Brake pedal: Fully released. Should exist.
Brake pedal: Slightly depressed. Should not exist.
SEC0 23 D
Condition Continuity
Clutch pedal: Fully released. Should exist.
Clutch pedal: Slightly depressed. Should not exist.
SEC0 23 D
Page 1718 of 2896
ASCD BRAKE SWITCH
EC-549
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Revision: June 20062007 Versa
ASCD BRAKE SWITCHPFP:25320
Component DescriptionUBS00QNW
When depress on the brake pedal, ASCD brake switch (2) is turned
OFF and stop lamp switch (1) is turned ON. ECM detects the state of
the brake pedal by this input of two kinds (ON/OFF signal)
Refer to EC-28, "
AUTOMATIC SPEED CONTROL DEVICE (ASCD)"
for the ASCD function.
CONSULT-II Reference Value in Data Monitor ModeUBS00QNX
Specification data are reference values.
BBIA0708E
MONITOR ITEM CONDITION SPECIFICATION
BRAKE SW1
(ASCD brake switch)
Ignition switch: ON
Brake pedal: Fully released (A/T, CVT)
Brake pedal and clutch pedal: Fully
released (M/T)ON
Brake pedal: Slightly depressed (A/T, CVT)
Brake pedal and/or clutch pedal: Slightly
depressed (M/T)OFF
BRAKE SW2
(Stop lamp switch)
Ignition switch: ONBrake pedal: Fully released OFF
Brake pedal: Slightly depressed ON
Page 1720 of 2896
ASCD BRAKE SWITCH
EC-551
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EC
Revision: June 20062007 Versa
Specification data are reference values and are measured between each terminal and ground.
CAUTION:
Do not use ECM ground terminals when measuring input/output voltage. Doing so may result in dam-
age to the ECM's transistor. Use a ground other than ECM terminals, such as the ground.
TERMI-
NAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
99 R Stop lamp switch[Ignition switch: ON]
Brake pedal: Fully releasedApproximately 0V
[Ignition switch: ON]
Brake pedal: Slightly depressedBATTERY VOLTAGE
(11 - 14V)
100 G ASCD brake switch[Ignition switch: ON]
Brake pedal: Slightly depressed (A/T, CVT)
Brake pedal and/or clutch pedal: Slightly
depressed (M/T) Approximately 0V
[Ignition switch: ON]
Brake pedal: Fully released (A/T, CVT)
Brake pedal and clutch pedal: Fully released
(M/T)BATTERY VOLTAGE
(11 - 14V)
Page 1721 of 2896

EC-552Revision: June 2006
ASCD BRAKE SWITCH
2007 Versa
Diagnostic ProcedureUBS00QNZ
1. CHECK OVERALL FUNCTION-I
With CONSULT-II
1. Turn ignition switch ON.
2. Select “BRAKE SW1” in “DATA MONITOR” mode with CON-
SULT-II.
3. Check “BRAKE SW1” indication under the following conditions.
M/T models
A/T and CVT models
Without CONSULT-II
1. Turn ignition switch ON.
2. Check voltage between ECM terminal 100 and ground under the
following conditions.
M/T models
A/T and CVT models
OK or NG
OK >> GO TO 2.
NG (M/T models) >>GO TO 3.
NG (A/T and CVT models) >>GO TO 4.
CONDITION INDICATION
Clutch pedal and/or brake pedal: Slightly depressed OFF
Clutch pedal and brake pedal: Fully released ON
CONDITION INDICATION
Brake pedal: Slightly depressed OFF
Brake pedal: Fully released ON
CONDITION VOLTAGE
Clutch pedal and/or brake pedal: Slightly depressed Approximately 0V
Clutch pedal and brake pedal: Fully released Battery voltage
CONDITION VOLTAGE
Brake pedal: Slightly depressed Approximately 0V
Brake pedal: Fully released Battery voltage
SEC0 11D
PBIB3315E