Service Precautions

WARNING: This page is about a different car, the 1995 Jeep Wrangler and 1995 Jeep Cherokee. However, it is still accessible from the selected car via links, so may be relevant.

Before proceeding with diagnosis, the following precautions must be followed:

Always wear safety glasses for eye protection.
Ensure ignition switch is in OFF position unless test procedure requires it to be on.
Fuel system is under constant fuel pressure. ALWAYS relieve fuel pressure before disconnecting any fuel injection-related component. DO NOT allow fuel to contact engine or electrical components. See FUEL PRESSURE RELEASE .
DO NOT wear rings, watches, loose hanging jewelry or loose clothing. Keep away from moving engine parts, fan and drive belts.
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 DTCs, making diagnosis of original problem more difficult.
DO NOT use a test light instead of a voltmeter.
When checking for spark, hold coil wire using insulated pliers. Position coil wire approximately 1/2" from ground. If coil wire is more than 1/2" from ground, damage to vehicle electronics and/or PCM may result.
DO NOT prolong testing of fuel injectors or engine may hydrostatically (liquid) lock.
Always repair lowest DTC number or first fault displayed (scan tool) first.
Always perform VERIFICATION TEST after repairs are made.
Always disconnect scan tool after use.
Always disconnect scan tool before charging battery.