Self-Diagnostic System: Precautions

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

Before proceeding with diagnosis, observe following precautions:

Ensure battery is fully charged and charging system is functional.
Probe PCM connector from pin side. DO NOT backprobe PCM connector.
DO NOT cause short circuits when performing electrical tests. This will set additional DTCs, making diagnosis of original problem more difficult.
DO NOT use a test light in place of a voltmeter.
Always begin repair with lowest DTC number (MIL) or first DTC displayed on scan tool.
Always perform verification test after repairs are made.
Always disconnect scan tool after use.
Always disconnect scan tool before charging battery.