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.
How To Proceed With Troubleshooting
HINT:
Use this procedure to troubleshoot the engine immobilizer system.
The hand-held tester should be used in steps 4, 5 and 7.
- VEHICLE BROUGHT TO WORKSHOP
- GO TO NEXT STEP
- CUSTOMER PROBLEM ANALYSIS CHECK AND SYMPTOM CHECK (See CUSTOMER PROBLEM ANALYSIS CHECK
)
- GO TO NEXT STEP
- CRANK ENGINE FOR MORE THAN 10 SECONDS
- GO TO NEXT STEP
- CHECK FOR DTC
- Check for DTCs and note any codes that are output.
- Delete the DTC.
- Recheck for DTCs. Try to prompt the DTC (SFI system and engine immobilizer system) by simulating the original activity that the DTC suggested.
- If the DTC does not reoccur, proceed to A.
- If the DTC (SFI system) reoccurs, proceed to B.
- If the DTC (engine immobilizer system) reoccurs, proceed to C.
B: Go to SFI SYSTEM (See HOW TO PROCEED WITH TROUBLESHOOTING )
C: Go to step 8
A: Go to next step.
- READ VALUE OF HAND-HELD TESTER (IMMOBILIZER ECU (TRANSPONDER KEY ECU ASSY) (SWITCH CONDITION))
- Connect the hand-held tester to the DLC3.
- Turn the ignition switch ON and push the hand-held tester main switch ON.
- Select the item KEY SW in the DATA LIST and read its value displayed on the hand-held tester.
Transponder key ECU
NG: Go to DTC B2780 (See DTC B2780 PUSH SWITCH/KEY UNLOCK WARNING SWITCH MALFUNCTION )
OK: Go to next step.
- PROBLEM SYMPTOMS TABLE (See PROBLEM SYMPTOMS TABLE
)
- If the fault is not listed on the problem symptoms table, proceed to A.
- If the fault is listed on the problem symptoms table, proceed to B.
B: Go to step 8
A: Go to next step.
- OVERALL ANALYSIS AND TROUBLESHOOTING
- Pre-check (See PRE-CHECK
)
- Inspection with the hand-held tester (ECU DATA MONITOR).
- Inspection with the hand-held tester (ACTIVE TEST).
- Terminals of ECU (See TERMINALS OF ECU )
- Pre-check (See PRE-CHECK
)
- DTC CHART (See DIAGNOSTIC TROUBLE CODE CHART
)
- GO TO NEXT STEP
- ADJUST, REPAIR OR REPLACE
- GO TO NEXT STEP
- CONFIRMATION TEST
END
NO RELATED
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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.