Pretest Inspection & Diagnostic Procedure

Following precautions and procedures must be followed:

• Always follow air bag service precautions to avoid air bag deployment and possible personal injury. See SERVICE PRECAUTIONS.
• After component replacement, ensure proper system operation. See SYSTEM OPERATION CHECK.
• When testing voltage or continuity at ACM, use terminal side (not wire end) of connector. DO NOT probe wire through insulation.
• Always check if any TECH SERVICE BULLETINS (TSBs) apply to vehicle.
• When using diagnostic charts, DO NOT skip any steps in chart or incorrect diagnosis may result. Always start at TEST 1A - TESTING SYSTEM FUNCTION. Starting with any other test may result in incorrect diagnosis. Always perform TEST VER-1 - VERIFICATION TEST after repairs are made. For a description of fault codes, see DIAGNOSTIC FAULT CODES (MESSAGES).
• Always use most current diagnostic program cartridge available to prevent erroneous codes or test results.
• When using diagnostic charts, use DRB voltmeter unless instructed to use an external voltmeter. Never use a test light in place of a voltmeter.
• When performing electrical tests, prevent accidental shorting of terminals. Such shorts can damage fuses or components and may cause a second code to be set, making diagnosis of original problem more difficult.
• Vehicle must have a fully-charged battery and functional charging system.
• Each time a connector is disconnected, inspect it to ensure it is in good condition. Always focus on circuit being tested. Dirt, water and corrosion are most common problems in connectors, causing voltage drop, open circuits and other improper operation.
• Always disconnect DRB after use.
• Always disconnect DRB before charging battery.