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.
Key Switch Check
- CHECK KEY SWITCH INPUT SIGNAL
With CONSULT-III
Check key switch "KEY ON SW" in DATA MONITOR mode with CONSULT-III. Refer to "CONSULT-III FUNCTION (BCM) ".
- When key is inserted into ignition key cylinder:
KEY ON SW : ON
- When key is removed from ignition key cylinder:
KEY ON SW : OFF
Without CONSULT-III
Check voltage between BCM connector and ground.
VOLTAGE SPECIFICATIONConnector Terminals Condition Voltage (V) (Approx.) (+) (-) M18 37 Ground Key is inserted. Battery voltage Key is removed. 0 OK or NG
OK: Key switch circuit is OK.
NG: GO TO 2.
- When key is inserted into ignition key cylinder:
- CHECK KEY SWITCH
- Turn ignition switch OFF.
- Disconnect key switch connector.
- Check key switch.CONTINUITY CHART
Terminals Condition Continuity 1 - 2 Key is inserted. Yes Key is removed. No OK or NG
OK: Check the following.
- 10A fuse [No. 19, located in fuse block (J/B)]
- Harness for open or short between key switch and fuse
- Harness for open or short between BCM and key switch
NG: Replace key switch.
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.