Diagnostic Circuit Check
The Diagnostic Circuit Check is an organized approach to identifying a problem created by an electronic control system malfunction. If after completing diagnostic circuit check and finding on-board diagnostics functioning properly (with no trouble codes displayed), a comparison of "Typical Scan Values", for the appropriate engine, may be used for comparison. The "Typical Values" are an average of display values recorded from normal operating vehicles and are intended to represent what a normal functioning system would display.