Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Diagnosis Procedure
- CHECK OVERALL FUNCTION-I
With CONSULT
- Turn ignition switch ON.
- Select "BRAKE SW1" in "DATA MONITOR" mode with CONSULT.
- Check "BRAKE SW1" indication under the following conditions.
BRAKE SWITCH INDICATION CONDITIONS (M/T MODELS)Condition INDICATION Clutch pedal and/or brake pedal: Slightly depressed OFF Clutch pedal and brake pedal: Fully released ON BRAKE SWITCH INDICATION CONDITIONS (CVT MODELS)Condition INDICATION Brake pedal: Slightly depressed OFF Brake pedal: Fully released ON Without CONSULT
- Turn ignition switch ON.
- Check voltage between ECM terminal 110 and ground under the following conditions.
VOLTAGE REFERENCE CHART (M/T MODELS)Condition VOLTAGE Clutch pedal and/or brake pedal: Slightly depressed Approximately 0 V Clutch pedal and brake pedal: Fully released Battery voltage VOLTAGE REFERENCE CHART (CVT MODELS)Condition VOLTAGE Brake pedal: Slightly depressed Approximately 0 V Brake pedal: Fully released Battery voltage OK or NG
OK: GO TO 2.
NG: GO TO 3.
- CHECK OVERALL FUNCTION-II
With CONSULT
Check "BRAKE SW2" indication in "DATA MONITOR" mode.
Condition INDICATION Brake pedal: Fully released OFF Brake pedal: Slightly depressed ON Without CONSULT
Check voltage between ECM terminal 106 and ground under the following conditions.
Condition VOLTAGE Brake pedal: Fully released Approximately 0 V Brake pedal: Slightly depressed Battery voltage OK or NG
OK: INSPECTION END
NG: GO TO 11.
- CHECK ASCD BRAKE SWITCH POWER SUPPLY
- Turn ignition switch OFF.
- Disconnect ASCD brake switch (1) harness connector.
- Stop lamp switch (2)
- Brake pedal (3)
- Turn ignition switch ON.
- Check voltage between ASCD brake switch terminal 1 and ground with CONSULT or tester.
Voltage: Battery voltage
OK or NG
OK: GO TO 8.
NG (M/T models) >>GO TO 4.
NG (CVT models) >> GO TO 6.
- CHECK ASCD CLUTCH SWITCH POWER SUPPLY CIRCUIT
- Turn ignition switch OFF.
- Disconnect ASCD clutch switch (1) harness connector.
- Clutch pedal (2)
- Turn ignition switch ON.
- Check voltage between ASCD clutch switch terminal 1 and ground with CONSULT or tester.
Voltage: Battery voltage
OK or NG
OK: GO TO 7.
NG: GO TO 5.
- DETECT MALFUNCTIONING PART
Check the following.
- 10A fuse
- Harness for open or short between ASCD clutch switch and fuse
Repair open circuit or short to ground or short to power in harness or connectors.
- DETECT MALFUNCTIONING PART
Check the following.
- 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.
- CHECK ASCD CLUTCH SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
- Turn ignition switch OFF.
- Check harness continuity between ASCD brake switch terminal 1 and ASCD clutch switch terminal 2. Refer to Wiring Diagram .
Continuity should exist .
- 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.
- CHECK ASCD BRAKE SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
- Turn ignition switch OFF.
- Disconnect ECM harness connector.
- Check harness continuity between ECM terminal 110 and ASCD brake switch terminal 2. Refer to Wiring Diagram .
Continuity should exist .
- Also check harness for short to ground and short to power.
OK or NG
OK: GO TO 9.
NG: Repair open circuit or short to ground or short to power in harness or connectors.
- CHECK ASCD BRAKE SWITCH
Refer to "COMPONENT INSPECTION ".
OK or NG
OK: GO TO 15.
NG: Replace ASCD brake switch. Refer to , "REMOVAL AND INSTALLATION ".
- CHECK ASCD CLUTCH SWITCH
Refer to "COMPONENT INSPECTION "
OK or NG
OK: GO TO 15.
NG: Replace ASCD clutch switch. Refer to , "REMOVAL AND INSTALLATION ".
- CHECK STOP LAMP SWITCH POWER SUPPLY CIRCUIT
- Turn ignition switch OFF.
- Disconnect stop lamp switch (2) harness connector.
- ASCD brake switch (1)
- Brake pedal (3)
- Check voltage between stop lamp switch terminal 1 and ground with CONSULT or tester.
Voltage: Battery voltage
OK or NG
OK: GO TO 13.
NG: GO TO 12.
- DETECT MALFUNCTIONING PART
Check the following.
- 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.
- CHECK STOP LAMP SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
- Disconnect ECM harness connector.
- Check harness continuity between ECM terminal 106 and stop lamp switch terminal 2. Refer to Wiring Diagram .
Continuity should exist .
- Also check harness for short to ground and short to power.
OK or NG
OK: GO TO 14.
NG: Repair open circuit or short to ground or short to power in harness or connectors.
- CHECK STOP LAMP SWITCH
Refer to "COMPONENT INSPECTION "
OK or NG
OK: GO TO 15.
NG: Replace stop lamp switch. Refer to , "REMOVAL AND INSTALLATION ".
- CHECK INTERMITTENT INCIDENT
Refer to TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT .
INSPECTION END
Use the Manual With the Right Hardware
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.
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