W/Harness Inspection

P0271 Cylinder 4 Injector Circuit High

Inspection/Repair - W/Harness Inspection

Terminal and Connector Inspection

1. Many malfunctions in the electrical system are caused by poor harness and terminals. Faults can also be caused by interference from other electrical systems, and mechanical or chemical damage.
2. Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage.
3. Has a problem been found?






Control Circuit Inspection

Check voltage
1. IG "OFF" and disconnect injector connector.
2. IG "ON".
3. Measure voltage between injector control terminal of injector harness connector and chassis ground.

Specification :Approx. 0 V





4. Is the measured voltage within specification?





Check short to battery in harness
1. IG "OFF" and disconnect injector connector and ECM connector.
2. Measure resistance between power and control terminals of injector harness connector.

Specification :Infinite





3. Is the measured resistance within specification?