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.
Component Function Check
- CHECK ASCD BRAKE SWITCH FUNCTION
WITH CONSULT
- Turn ignition switch ON.
- Select "BRAKE SW1" in "DATA MONITOR" mode with CONSULT.
- Check "BRAKE SW1" indication under the following conditions.
Monitor item
Condition
Indication
BRAKE SW1
(ASCD brake switch)
Brake pedal
Slightly depressed
OFF
Fully released
ON
WITHOUT CONSULT
- Turn ignition switch ON.
- Check the voltage between ECM harness connector terminals as per the following.
ECM
Condition
Voltage (V)
Connector
+
-
Terminal
Terminal
E20
140
(ASCD brake switch signal)
152
Brake pedal
Slightly depressed
Approx. 0
Fully released
Battery voltage
Is the inspection result normal?
YES
INSPECTION END
NO
Go to Diagnosis Procedure .
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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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