Service Precautions

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 PCM connector.
• DO NOT  cause short circuits when performing electrical tests. This will set additional fault codes, making diagnosis of original problem more difficult.
• Always repair lowest fault code number (CHECK ENGINE light) or first fault displayed (DRB) before repairing others.
• Always perform TEST VER-4A  after repairs are made.