Scan Tool Testing and Procedures

Displayed Input Status
The scan tool displays the status of the instrument cluster inputs. On the scan tool, select the instrument cluster status display and determine if the switched inputs can be properly interpreted. The display also indicates if the input has changed states. For example, when the engine coolant level is OK, the scan tool displays the input status of the engine coolant level switch as inactive. When the engine coolant level is low, the scan tool reads the input as active. Use this kind of information when diagnosing a malfunction associated with a particular instrument cluster input, or an input that is shared with another vehicle system.

Cycle Indicator and Gauges
Use a scan tool in order to cycle the instrument cluster indicators and gauges. This feature can be used to determine if the instrument cluster is able to cycle an indicator or gauge regardless of the inputs or any specific program instructions. Once a test is selected, the scan tool commands the instrument cluster to energize the selected indicator or gauge. The displayed information represents only what was instrument cluster commanded, not if an action has actually taken place. Check the instrument cluster for the ability to control each of the selected indicator and gauge functions.