Symptoms

- Engine Light ON (or Service Engine Soon Warning Light) - Transmission will not shift gears.

Possible Causes

- Faulty 3-4 shift solenoid valve - 3-4 shift solenoid valve harness or connectors - 3-4 shift solenoid valve circuit is open or shorted - Low transmission fluid level - Dirty transmission fluid

When Detected

The P0763 code is detected when the gear required by the ECM does not match the actual gear when vehicle is driven.

Description

3-4 Shift solenoid valve is turned ON or OFF by the Transmission Control Module (TCM) in response to signals sent from the park/neutral position (PNP) switch, vehicle speed and Engine Control Module (ECM) (throttle opening). Gears will then be shifted to the optimum position.