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.
Detailed Flow
- INTERVIEW FROM THE CUSTOMER
Clarify customer complaints before inspection. First of all, perform an interview utilizing DIAGNOSTIC WORK SHEET and reproduce symptoms as well as fully understand it. Ask customer about his/her complaints carefully. Check symptoms by driving vehicle with customer, if necessary.
CAUTION:Customers are not professional. Never guess easily like "maybe the customer means that...," or "maybe the customer mentions this symptom".
GO TO STEP 2 .
- CHECK SYMPTOM
Reproduce the symptom that is indicated by the customer, based on the information from the customer obtained by interview. Also check that the symptom is not caused by protection function. Refer to PROTECTION FUNCTION .
CAUTION:When the symptom is caused by normal operation, fully inspect each portion and obtain the understanding of customer that the symptom is not caused by a malfunction.
GO TO STEP 3 .
- PERFORM SELF-DIAGNOSIS
With CONSULT
Perform self-diagnosis.
Is any DTC detected?
YES
Record or print DTC and freeze frame data (FFD). GO TO STEP 4 .
NO
GO TO STEP 6 .
- RECHECK SYMPTOM
- Erase self-diagnostic results.
- Perform DTC confirmation procedures for the malfunctioning system.
NOTE:If some DTCs are detected at the same time, determine the order for performing the diagnosis based on DTC INSPECTION PRIORITY CHART .
Is any DTC detected?
YES
GO TO STEP 5 .
NO
Check harness and connectors based on the information obtained by interview. Refer to INTERMITTENT INCIDENT .
- REPAIR OR REPLACE MALFUNCTIONING PARTS
- Repair or replace malfunctioning parts.
- Reconnect part or connector after repairing or replacing.
- When DTC is detected, erase self-diagnostic results for "EPS".
GO TO STEP 7 .
- IDENTIFY MALFUNCTIONING SYSTEM BY SYMPTOM DIAGNOSIS
Estimate malfunctioning system based on symptom diagnosis and perform inspection.
Can the malfunctioning system be identified?
YES
GO TO STEP 7 .
NO
Check harness and connectors based on the information obtained by interview. Refer to INTERMITTENT INCIDENT .
- FINAL CHECK
- Check the reference value for EPS control unit.
- Recheck the symptom and check that symptom is not reproduced on the same conditions.
Is the symptom reproduced?
YES
GO TO STEP 3 .
NO
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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