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.
Confirmation Procedure
- CHECK DTC PRIORITY
If DTC P0123 is displayed with DTC P0643, first perform the confirmation procedure (trouble diagnosis) for DTC P0643.
Is DTC P0643 detected?
YES
Perform diagnosis of applicable. Refer to DTC Description .
NO
GO TO 2.
- PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following procedure before conducting the next test.
- Turn ignition switch OFF and wait at least 10 seconds.
- Turn ignition switch ON.
- Turn ignition switch OFF and wait at least 10 seconds.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 10 V at idle.
GO TO 3.
- PERFORM DTC CONFIRMATION PROCEDURE
- Start engine and let it idle for 1 second.
- Check DTC.
Is DTC P0123 detected?
YES
Refer to DTC Diagnosis Procedure .
NO
To check malfunction symptom before repair: Refer to Inspection .
NO
Confirmation after repair: INSPECTION END
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
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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.