How to Reset a Transmission Controller


1. Place the vehicle's transmission into park and turn off the engine. Set the parking brake and turn the ignition to the 'ON' position, but don't crank or start the engine.
2. Plug an automotive scan tool into the vehicle's diagnostic communications port. This port is generally located underneath the dashboard on the driver's side of the vehicle, just below the steering column.
3. Press the power button on the scan tool and wait for it to boot up. Select 'Transmission' from the scan tool's main menu screen, and then choose 'Transmission Controller.' Select 'Clear all Current and Stored Codes.'
4. Disconnect the scan tool from the vehicle and start the engine. Confirm that the 'Service Vehicle' light is not illuminated. The transmission controller is now reset.