ASCD Brake Switch

ASCD BRAKE 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). System Description for the ASCD function.




Component Function Check
1.CHECK ASCD BRAKE SWITCH FUNCTION
With CONSULT-III
1. Turn ignition switch ON.
2. Select "BRAKE SW1" in "DATA MONITOR" mode with CONSULT-III.
3. Check "BRAKE SW1" indication under the following conditions.





Without CONSULT-III
1. Turn ignition switch ON.
2. Check the voltage between ECM harness connector terminals as per the following.





Is the inspection result normal?
YES - INSPECTION END
NO - Go to SEE Diagnosis Procedure.




Diagnosis Procedure
1.INSPECTION START
Check which type of transmission the vehicle is equipped with.
Which type of transmission?
A/T models or M/T models and synchrorev match mode-GO TO 2.
M/T models without synchrorev match mode-GO TO 7.
2.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 the voltage between ASCD brake switch harness connector and ground.





Is the inspection result normal?
YES - GO TO 4.
NO - GO TO 3.
3.DETECT MALFUNCTIONING PART
Check the following.
- Fuse block (J/B) connector E103
- 10 A fuse (No. 3)
- Harness for open or short between ASCD brake switch and fuse
- Repair open circuit or short to ground in harness or connectors.
4.CHECK ASCD BRAKE SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check the continuity between ASCD brake switch harness connector and ECM harness connector.





4. Also check harness for short to ground and short to power.
Is the inspection result normal?
YES - GO TO 6.
NO - GO TO 5.
5.DETECT MALFUNCTIONING PART
Check the following.
- Harness connectors E106, M6
- Harness for open or short between ECM and ASCD brake switch
- Repair open circuit, short to ground or short to power in harness or connectors.
6.CHECK ASCD BRAKE SWITCH
SEE Component Inspection (ASCD Brake Switch)
Is the inspection result normal?
YES - GO TO 15.
NO - Replace ASCD brake switch.
7.CHECK ASCD BRAKE SWITCH CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect ASCD brake switch harness connector.
3. Turn ignition switch ON.
4. Check the voltage between ASCD brake switch harness connector and ground.





Is the inspection result normal?
YES - GO TO 12.
NO - GO TO 8.
8.CHECK ASCD BRAKE SWITCH POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect clutch pedal position switch harness connector.
3. Turn ignition switch ON.
4. Check the voltage between clutch pedal position switch harness connector and ground.





Is the inspection result normal?
YES - GO TO 10.
NO - GO TO 9.
9.DETECT MALFUNCTIONING PART
Check the following.
- Fuse block (J/B) connector E103
- 10 A fuse (No. 3)
- Harness for open or short between clutch pedal position switch and fuse
- Repair open circuit or short to ground in harness or connectors.
10.CHECK ASCD BRAKE SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Check the continuity between clutch position switch harness connector and ASCD brake switch harness connector.





3. Also check harness for short to ground and short to power.
Is the inspection result normal?
YES - GO TO 11.
NO - Repair open circuit, short to ground or short to power in harness or connectors.
11.CHECK CLUTCH PEDAL POSITION SWITCH
SEE Component Inspection (Clutch Pedal Position Switch).
Is the inspection result normal?
YES - GO TO 15.
NO - Replace clutch pedal position switch.
12.CHECK ASCD BRAKE SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check the continuity between ASCD brake switch harness connector and ECM harness connector.





4. Also check harness for short to ground and short to power.
Is the inspection result normal?
YES - GO TO 14.
NO - GO TO 13.
13.DETECT MALFUNCTIONING PART
Check the following.
- Harness connectors E106, M6
- Harness for open or short between ECM and ASCD brake switch
- Repair open circuit, short to ground or short to power in harness or connectors.
14.CHECK ASCD BRAKE SWITCH
SEE Component Inspection (ASCD Brake Switch).
Is the inspection result normal?
YES - GO TO 15.
NO - Replace ASCD brake switch.
15.CHECK INTERMITTENT INCIDENT
Intermittent Incident Regular Grade.
- INSPECTION END




Component Inspection (ASCD Brake Switch)
1.CHECK ASCD BRAKE SWITCH-I
1. Turn ignition switch OFF.
2. Disconnect ASCD brake switch harness connector.
3. Check the continuity between ASCD brake switch terminals under the following conditions.





Is the inspection result normal?
YES - INSPECTION END
NO - GO TO 2.
2.CHECK ASCD BRAKE SWITCH-II
1. Adjust ASCD brake switch installation. Inspection After Removal.
2. Check the continuity between ASCD brake switch terminals under the following conditions.





Is the inspection result normal?
YES - INSPECTION END
NO - Replace ASCD brake switch.




Component Inspection (Clutch Pedal Position Switch)
1.CHECK CLUTCH PEDAL POSITION SWITCH-I
1. Turn ignition switch OFF.
2. Disconnect clutch pedal position switch harness connector.
3. Check the continuity between clutch pedal position switch terminals under the following conditions.





Is the inspection result normal?
YES - INSPECTION END
NO - GO TO 2.
2.CHECK CLUTCH PEDAL POSITION SWITCH-II
1. Adjust clutch pedal position switch installation. Adjustments.
2. Check the continuity between clutch pedal position switch terminals under the following conditions.





Is the inspection result normal?
YES - INSPECTION END
NO - Replace clutch pedal position switch.