Resetting the check-engine light on your Toyota car needs to be done after you've finished fixing your Toyota car. The check-engine light only comes on when there is a problem with the vehicle's emissions system or other system components of your Toyota car.XPROG V5.70 Replacement parts can normally be purchased at any auto-parts store. To reset the check-engine light, you can use a special tool, also available from any auto-parts store, called an onboard diagnostic scan (OBD) tool. This tool is the only tool capable of reading the trouble codes and then clearing the Toyota car trouble codes by connecting directly to the computer. 

Remove the negative battery cable by turning the attached bolt until it is loose enough to remove. Slide a non-conductive object between the battery and the cable, such as a newspaper, book or magazine. Ford VCM II This prevents the cable from possibly coming back into contact with the battery.

Turn the ignition on for a few seconds, then turn it back off and remove the key. Nothing will happen since the battery is disconnected, but this action depletes any excess energy from the electrical system, allowing the computer to reset faster.

Reverse the previous steps to reconnect the battery cable. Confirm the bolt has been securely tightened before closing the hood.

Start the engine and allow the Sienna to idle for at least 2 minutes before driving. Auto key Programmer The engine light will no longer illuminate. If it comes back on, then the problem that triggered the light has not been resolved and additional repairs are in order.