IN−26 − INTRODUCTION HOW TO TROUBLESHOOT ECU CONTROLLED SYSTEMS Taking into account the points on the previous page, a flow chart showing how to proceed with troubleshoot- ing using the diagnostic trouble code check is shown below. This flow chart shows how to utilize the diagnos- tic trouble code check effectively, then by carefully checking the results, indicates how to proceed either to diagnostic trouble code troubleshooting or to troubleshooting of problem symptoms table.
Diagnostic trouble code check Making a note of and clearing of the diagnostic trouble codes displayed Symptom confirmation No problem symptoms exist Problem symptoms exist Simulation test using the symptom simulation methods Diagnostic trouble code check Diagnostic trouble code displayed Problem symptoms exist Normal code displayed Problem symptoms exist Normal code displayed No problem symptoms exist Troubleshooting of problem indicated by diagnostic trouble code System Normal Troubleshooting of each problem symptom If a diagnostic trouble code was displayed in the initial diagnostic trouble code check, it indicates that the trouble may have occurred in a wire harness or connector in that circuit in the past.
Therefore, check the wire harness and con- nectors (See page IN−33 ). 26 Author : Date: