Diagnostic Tests: Notes
CAUTION:
If engine control module (ECM) replacement is instructed in following tests, always ensure ECM electrical connectors and ground circuits are okay. If either are defective, repair and repeat testing to confirm ECM malfunction. On models equipped with engine immobilizer, if ECM is replaced, ECM must be programmed with proper ignition key code for engine immobilizer system. For programming procedures, see COMPUTER RELEARN article in GENERAL INFORMATION, or appropriate ENGINE IMMOBILIZER SYSTEMS article in ACCESSORIES & EQUIPMENT.
NOTE:
Before performing any diagnostic test, see SELF-DIAGNOSTIC SYSTEM for diagnostic system functions and system diagnostic procedures. Also check for any relate Technical Service Bulletins (TSBs).
NOTE:
When performing diagnostic tests, it may be necessary to identify Engine Control Module (ECM) electrical connector terminals which are referenced to in testing procedure. See Fig 1.