Diagnostic Tests: Notes

NOTE: Before performing any diagnostic test, see SELF-DIAGNOSTICS - INTRODUCTION article for diagnostic system functions and system diagnostic procedures. For component location, see appropriate illustration in THEORY & OPERATION article. To identify circuits and wire colors referenced in testing, see WIRING DIAGRAMS article.

CAUTION: If ECM replacement is instructed in following testing, always ensure ECM connectors and ground circuit are okay. If either are suspect, repair and repeat testing to confirm ECM malfunction.

NOTE: To identify ECM terminals referenced in testing, see illustration. See Fig 1.

Fig 1: Identifying Engine Control Module (ECM) Connector Terminals