Service Precautions

CAUTION: When battery is disconnected, vehicle computer and memory systems may lose memory data. Driveability problems may exist until computer systems have completed a relearn cycle. See COMPUTER RELEARN PROCEDURES article in the GENERAL INFORMATION section before disconnecting battery.

Before proceeding with diagnosis, observe following precautions:

Vehicle must have a fully charged battery and functional charging system.
Probe PCM 60-pin connector from pin side. DO NOT backprobe the PCM connector.
DO NOT cause short circuits when performing electrical tests. This will set additional fault codes, making diagnosis of the original problem more difficult.
Always repair lowest fault code number (CHECK ENGINE light) or first fault displayed (DRB-II) before repairing others.
Always perform VERIFICATION PROCEDURE SC-VER under SELF-DIAGNOSTIC TESTS after repairs are made.