W/Harness Inspection

Engine Control
P0503 Vehicle Speed Sensor A Intermittent/Erratic/High - 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?






Signal Circuit Inspection

Check Short to Ground
1. IG "OFF" and disconnect ECM connector and ESC (ESP) control module connector.
2. Measure resistance between vehicle speed input signal terminal of ECM harness connector and chassis ground.

Specification : Infinite




3. Is the measured resistance within specification?





Check short to battery in harness
1. IG "OFF" and disconnect ECM connector and ESC (ESP) control module connector.
2. IG "ON".
3. Measure the voltage between signal terminal of ESC (ESP) control module connector and chassis ground.

Specification : Approx. 0 V




4. Is the measured voltage within specification?