Pretest Inspection

Before diagnosis, following precautions must be followed:

• Vehicle must have a fully charged battery and functional charging system.
• Always start at TEST 1A: IDENTIFYING VEHICLE EQUIPMENT & SYSTEM PROBLEMS. Starting with any other test may result in incorrect results.
• Only perform test steps indicated. It is NOT necessary to perform all steps in a test.
• VEHICLE COMMUNICATIONS tests should only be used when instructed to do so by another test. Always start at TEST 1A: GENERAL FAILURE MESSAGES.
• Always perform verification procedure test after repairs are made.
• At end of each test step, reconnect all wires and install any components removed for testing.
• Use extreme care when connecting or disconnecting wiring during testing to prevent accidental grounding or shorting.
• DO NOT use a test light in place of a voltmeter.
• Always disconnect DRB-II after use.
• Always disconnect DRB-II before charging battery.