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.
Fuel Injector Circuit
- Check or repair only faulty parts.
- After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to OPERATION , Clear Memory Mode.>, and Inspection Mode <Ref. to PROCEDURE , Inspection Mode.>.
- Use the check board when measuring the ECM terminal voltage and resistance.
WIRING DIAGRAM:
Engine Electrical System <Ref. to WIRING DIAGRAM , Engine Electrical System.>
| Step | Check | Yes | No |
|---|---|---|---|
| 1 CHECK OPERATION OF EACH FUEL INJECTOR. While cranking the engine, check each fuel injector emits operating sound. Use a sound scope or listen by attaching a screwdriver to the injector for this check. |
Does the fuel injector emit operating sound? | Check the fuel pressure. <Ref. to INSPECTION , Fuel Pressure.> | Go to step 2 . |
2 CHECK HARNESS BETWEEN ECM AND FUEL INJECTOR CONNECTOR.
|
Is the resistance less than 1 Ω? | Go to step 3 . | Repair the open circuit of the harness between the ECM connector and fuel injector connector. |
| 3 CHECK HARNESS BETWEEN ECM AND FUEL INJECTOR CONNECTOR. Measure the resistance of harness between ECM connector and chassis ground. Connector & terminal #1 (E158) No. 12 - Chassis ground: #1 (E158) No. 11 - Chassis ground: #2 (E158) No. 24 - Chassis ground: #2 (E158) No. 23 - Chassis ground: #3 (E158) No. 36 - Chassis ground: #3 (E158) No. 35 - Chassis ground: #4 (E158) No. 48 - Chassis ground: #4 (E158) No. 47 - Chassis ground: |
Is the resistance 1 MΩ or more? | Go to step 4 . | Repair the short circuit to ground in harness between ECM connector and fuel injector connector. |
| 4 CHECK EACH FUEL INJECTOR. Check each fuel injector. <Ref. to INSPECTION , Fuel Injector.> |
Is the check result OK? | Go to step 5 . | Replace the faulty fuel injector. <Ref. to Fuel Injector .> |
| 5 CHECK FOR POOR CONTACT. Check for poor contact of ECM connector. |
Is there poor contact of ECM connector? | Repair the poor contact of ECM connector. | Inspection using "General Diagnostic Table". <Ref. to INSPECTION , General Diagnostic Table.> |
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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