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 procedures under 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 procedures at TEST 1A - IDENTIFYING SYSTEM PROBLEMS  . Starting with any other test may result in incorrect diagnosis. Always perform SYSTEM OPERATION CHECK  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 volt meter unless instructed to use an external volt meter. Never use a test light in place of a volt meter.
• 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.
• Always disconnect DRB after use.
• Always disconnect DRB before charging battery.