ASCD Brake Switch

ASCD BRAKE SWITCH





Component 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 this input of two kinds (ON/OFF signal). System Description for the ASCD function.




Diagnosis Procedure
1.CHECK OVERALL FUNCTION-I
With CONSULT-III
1. Turn ignition switch ON.
2. Select "BRAKE SW 1" in "DATA MONITOR" mode with CONSULT-III.
3. Check "BRAKE SW 1" indication under the following conditions.





Without CONSULT-III
1. Turn ignition switch ON.





2. Check voltage between ECM terminal 108 and ground under the following conditions.





OK or NG
OK - GO TO 2.
NG - GO TO 3.
2.CHECK OVERALL FUNCTION-II
With CONSULT-III
Check "BRAKE SW 2" indication in "DATA MONITOR" mode.





Without CONSULT-III
Check voltage between ECM terminal 101 and ground under the following conditions.










OK or NG
OK - INSPECTION END
NG - 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 voltage between ASCD brake switch terminal 1 and ground with CONSULT-III or tester.






OK or NG
OK - GO TO 5.
NG - GO TO 4.
4.DETECT MALFUNCTIONING PART
Check the following.
- Harness connectors M31, E152
- Fuse block (J/B) connector M4
- 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.
5.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 108 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 6.
NG - Repair open circuit or short to ground or short to power in harness or connectors.
6.CHECK ASCD BRAKE SWITCH
SEE Component Inspection.
OK or NG
OK - GO TO 11.
NG - Replace ASCD brake switch.
7.CHECK STOP LAMP SWITCH POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.





2. Disconnect stop lamp switch harness connector.





3. Check voltage between stop lamp switch terminal 1 and ground with CONSULT -III or tester.






OK or NG
OK - GO TO 9.
NG - GO TO 8.
8.DETECT MALFUNCTIONING PART
Check the following.
- Harness connectors M31, E152
- Fuse block (J/B) connector M60
- 10A fuse
- Harness for open or short between stop lamp switch and battery
- Repair open circuit or short to ground or short to power in harness or connectors.
9.CHECK STOP LAMP SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Disconnect ECM harness connector.
2. Check harness continuity between ECM terminal 101 and stop lamp switch terminal 2. Refer to Wiring Diagram.






3. 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 STOP LAMP SWITCH
SEE Component Inspection.
OK or NG
OK - GO TO 11.
NG - Replace stop lamp switch.
11.CHECK INTERMITTENT INCIDENT
Intermittent Incident and Intermittent Incident.
- INSPECTION END




Component Inspection

ASCD BRAKE SWITCH
1. Turn ignition switch OFF.
2. Disconnect ASCD brake switch harness connector.





3. Check harness continuity between ASCD brake switch terminals
1 and 2 under the following conditions.





If NG, adjust ASCD brake switch installation, Standard Pedal, and perform step
3 again.

STOP LAMP SWITCH
1. Turn ignition switch OFF.
2. Disconnect stop lamp switch harness connector.





3. Check harness continuity between stop lamp switch terminals 1 and 2 under the following conditions.





If NG, adjust stop lamp switch installation, Standard Pedal, and perform step
3 again.