Self-Diagnostic System Check
The SELF-DIAGNOSTIC SYSTEM CHECK is an organized approach for identifying a problem caused by the on-car computer-controlled electronics. Understanding the chart and using it correctly reduces diagnostic time and prevents unnecessary replacement of parts.
The SELF-DIAGNOSTIC SYSTEM CHECK should be used to BEGIN DIAGNOSIS if any customer complaint which DOES NOT directly relate to a specific suBsystem.
If the "ENGINE CONTROL SYSTEM" light fails to illuminate during cranking, then the problem could be in the power supply circuit of the BCM/ECM computer system. The SELF-DIAGNOSTIC SYSTEM CHECK will direct technician to an appropriate diagnostic chart.
If the CCDIC display is not operating properly, BCM/ECM COMPUTER SYSTEM SELF-DIAGNOSTICS mode CANNOT be used. In this case, the SELF-DIAGNOSTIC SYSTEM CHECK will direct technician to an appropriate diagnostic chart.
If a trouble code is identified the BCM/ECM computer system self-diagnostics mode, problem can be corrected following the appropriate numbered code chart(s). If no code has been identified, the SELF-DIAGNOSTIC SYSTEM CHECK will direct technician to an appropriate diagnostic chart.