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.
ECS Resistance Tests
The ECS can be checked using an volt/ohmmeter. Before making resistance tests, turn ignition off and disconnect wiring connectors at ECU. Insert volt/ohmmeter probes into wiring connectors from wire side. Measure resistance at connector terminals, NOT ECU terminals.
| Code No. | Probable Cause |
|---|---|
| 2 & 3 | Air Flow Meter or Circuit, ECU |
| 4 | Coolant Temp. Sensor or Circuit, ECU |
| 5 | Oxygen Sensor or Circuit, ECU |
| 6 | Ignition System Circuit, Distributor, Coil, Ignitor, ECU |
| 7 | Throttle Position Sensor or Circuit, ECU |
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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