Scan Tool (Special Functions)

WARNING: This page is about a different car, the 1999 GMC Sierra and 1999 Chevrolet Silverado. However, it is still accessible from the selected car via links, so may be relevant.

Use a scan tool in order to cycle the instrument cluster lamps, the gauges, and the PRNDL display functions. When the instrument cluster special functions is selected, the scan tool can command the cluster to cycle a lamp, a gauge, or the PRNDL display. Use this feature in order to dermine if the cluster is able to cycle an output regardless of the inputs or any specific program instructions. Once a test is selected, the scan tool will command the instrument cluster to energize the selected output. The scan tool then displays the status of the selected output. The displayed information represents only what the instrument cluster commanded, not what action was actually taken. Ensure the instrument cluster is actually performing each of the selected output functions.