Symptoms

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

Possible Causes

- Low transmission fluid level - Dirty transmission fluid - Faulty overdrive solenoid valve - Overdrive solenoid valve harness or connectors - Overdrive solenoid valve circuit is open or shorted

When Detected

The P0765 code is detected when the ECM detects an improper voltage drop when it tries to operate the solenoid valve.

Description

Overdrive 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.