* OBD-II Scanner: While your 1999 truck is OBD-II compliant, it's on the earlier end of the adoption. A generic OBD-II scanner *should* work, but some very basic, inexpensive ones might have trouble communicating. A more robust scanner is recommended. Plug the scanner into the OBD-II port (usually under the dash, but consult your owner's manual), and it will read the trouble codes (DTCs). This is the easiest and most reliable method.
* Paper Clip Method (Less Reliable): This method *might* work, but it's not guaranteed for all 1999 Chevy trucks and is less accurate than a scanner. It involves shorting two pins in the OBD-II port's diagnostic connector. You'll need to find a wiring diagram specific to your truck's year and model to identify the correct pins to short. Improperly performing this can damage your vehicle's computer. Search online for "1999 Chevy truck paperclip method" but proceed with caution. This method is generally used to get a single blink code (flash code). The blink pattern needs to be interpreted based on a code chart specific to your vehicle's system.
* Professional Diagnostic: Take your truck to a mechanic or auto parts store (like AutoZone or Advance Auto Parts) that offers free code reading services. This is often the easiest and most reliable option, as they have the right equipment and expertise.
Important Considerations:
* Owner's Manual: Consult your owner's manual. It might contain information about the OBD-II port location and, possibly, troubleshooting information.
* Year and Model Specificity: The exact procedures and code interpretations can vary slightly depending on the specific model of your 1999 Chevy truck (e.g., Silverado, S-10, etc.). Be sure to include this detail in any online searches.
Using an OBD-II scanner is strongly recommended for reliability and ease of use. The paperclip method is outdated and carries a risk of damaging your vehicle's system. A professional diagnostic is a reliable alternative if you lack the tools or confidence.
