ECM Power Source Circuit (Ignition On): Notes

NOTE: For information on engine immobilizer, see THEORY & OPERATION article.

CAUTION: If ECM replacement is instructed during any test procedures, always ensure ECM harness connector and ground circuit are okay. If either are suspect, repair and repeat testing to confirm ECM malfunction. If ECM is replaced, ECM must be programmed with proper ignition key code for engine immobilizer system. For programming procedures, see COMPUTER RELEARN PROCEDURES - LEXUS article in GENERAL INFORMATION.