Diagnosis (Normal Mode)

2003 Toyota 4 Runner 2WD V6-4.0L (1GR-FE)SECTION Diagnosis (Normal Mode)
INSPECT DIAGNOSIS (Normal Mode)







a. Check the MIL.
1. The MIL comes on when the ignition switch is turned ON and the engine is not running.

HINT: If the MIL does not light up, troubleshoot the combination meter.

2. When the engine is started, the MIL should go off. If the lamp remains on, it means that the diagnosis system has detected a malfunction or abnormality in the system.

b. Check the DTC.

NOTE: Hand-held tester only:
When the diagnostic system is switched from the normal mode to the check mode, all the DTCs and freeze frame data recorded in the normal mode will be erased. So before switching modes, always check the DTCs and freeze frame data, and note them down.

1. Prepare an OBD II scan tool (complying with SAE J1978) or hand-held tester.
2. Connect the OBD II scan tool or hand-held tester to the DLC3 at the lower of the instrument panel.
3. Turn the ignition switch ON and press the OBD II scan tool or hand-held tester switch ON.
4. Use the OBD II scan tool or hand-held tester to check the DTCs and freeze frame data and note them down (For operating instructions, see the OBD II scan tool's instruction book).
5. See Trouble Code Descriptions to confirm the details of the DTCs.

NOTE: When simulating symptoms with an OBD II scan tool (excluding hand-held tester) to check the DTCs, use the normal mode. For codes on the DTCs chart subject to "2 trip detection logic", turn the ignition switch OFF after the symptom is simulated once. Then repeat the simulation process again. When the problem has been simulated twice, the MIL is indicated on the instrument panel and DTCs are recorded in the ECM.
RENDER: 1.0x

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • β€’ You smell fuel, burning insulation, or see smoke.
  • β€’ Brakes feel soft, pull hard to one side, or make grinding noises.
  • β€’ The engine overheats, stalls repeatedly, or misfires under load.
  • β€’ You are missing required tools, torque specs, or safe lifting equipment.
  • β€’ You are not confident in the next step or safety outcome.