Your 1999 Chevrolet S10 features an industry standard OBD-II (Onboard Diagnostic Link) used to troubleshoot issues that are plaguing the vehicle. Your Chevrolet S10’s computer will save trouble codes for later retrieval whenever an issue arises and by using an aftermarket scan tool, you will be able to retrieve these trouble codes to see exactly what vehicle system or component is at fault. Because a trouble code displayed on a cheap consumer grade OBD-II scanner will not explain the meaning of a trouble code, you will need to look up their definitions either online or within the scanner's documentation.
Locate the OBD-II connector inside your vehicle. The OBD-II connector will be on the lower driver’s side portion of the dashboard, near the emergency brake pedal. Connect your OBD-II scanner into the diagnostic port.
Close all the vehicle's doors and roll up the windows. Turn on the scan tool and switch the ignition key to the “ON” position but do not start the vehicle.
Refer to your scan tool’s documentation for retrieving the trouble codes from your vehicle. Write down the trouble codes displayed by the scan tool with a pen and piece of paper. Refer to the trouble code section inside the documentation that came with your scan tool or click on the resource below for a list of trouble codes for your vehicle and explanations for them.
Switch the ignition back to the “OFF” position and turn off your scan tool. Remove the scan tool’s diagnostic cord from your S10’s OBD-II port.
