Self-Diagnostic System: Precautions

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 or probe wires through insulation.
• 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 (scan tool).
• Always perform verification test after repairs are made.
• Always disconnect scan tool after use.
• Always disconnect scan tool before charging battery.