The best way to Clear the "Service Engine Soon" Message on a GM Truck

Insert the key into the ignition in your GM truck and turn it to the "on" position. This is the position right before your engine starts.

Find the trapezoidal-shaped ">Auto diagnostic tool Link Connector under the dashboard near the steering column.

Plug the OBD scanner into the Diagnostic Link Connector. The vehicle's battery automatically turns on the scanner.

Locate the arrows on the face of the scanner and use them to scroll through the menu. Select "Read Codes" and write down the codes on a piece of paper.

Unplug the scanner and look up the trouble codes in a repair manual or take the codes to your mechanic autel-auto-scanner-cid153">Autel auto scanner. Have any repairs done on the vehicle before proceeding to the next step.

Repeat steps 1 through 3. Use the arrows to find the "Erase Codes" option; press this option.

Unplug the scanner and start the engine. The "Service Engine Soon" message should no longer be visible on the instrument panel.