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
The electrical load signal (Headlamp switch signal, rear window defogger switch signal, etc.) is transferred via the CAN communication line.
- CHECK REAR WINDOW DEFOGGER SWITCH FUNCTION
With CONSULT
- Turn ignition switch ON.
- On CONSULT screen, select "ENGINE">>"Data Monitor".
- Check "LOAD SIGNAL" indication under the following conditions.
Monitor item
Condition
Indication
LOAD SIGNAL
Rear window defogger switch
ON
ON
OFF
OFF
Is the inspection result normal?
YES
GO TO 2.
NO
Refer to Diagnosis Procedure .
- CHECK LIGHTING SWITCH FUNCTION
Check "LOAD SIGNAL" indication under the following conditions.
Monitor item
Condition
Indication
LOAD SIGNAL
Lighting switch
ON at 2nd position
ON
OFF
OFF
Is the inspection result normal?
YES
GO TO 3.
NO
Refer to Diagnosis Procedure .
- CHECK HEATER FAN CONTROL SWITCH FUNCTION
Select "HEATER FAN SW" and check indication under the following conditions.
Monitor item
Condition
Indication
HEATER FAN SW
Heater fan control switch
ON
ON
OFF
OFF
Is the inspection result normal?
YES
INSPECTION END
NO
Refer to Diagnosis Procedure .
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
Disclosure: Verified tool recommendations may earn an affiliate commission at no cost to you.
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.