Service Precautions

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

• Ensure fuel pressure is released before removing fuel line or fittings, as fuel system is under pressure and may cause personal injury.
• When using SELF-DIAGNOSTIC TESTS for diagnosis, DO NOT skip any steps, or incorrect diagnosis may result. Always perform indicated verification procedure after repairs are made.
• When using a jumper wire, ensure either jumper wire or circuit is fuse-protected.
• Before disconnecting connector from any control module, ensure ignition is off before removing connector.
• When checking voltage or continuity at any control module, probe connector for control module from pin side. DO NOT backprobe connector or probe wires through the insulation.
• DO NOT cause short circuits when performing electrical tests. This will set additional Diagnostic Trouble Codes (DTCs), making diagnosis of original problem more difficult.
• Use specific test equipment as specified when performing electrical tests.
• When checking for spark, ensure coil wire is NOT more than 1/4" from engine ground. If coil wire is more than 1/4" from engine ground, damage to vehicle electronics and/or PCM may result.
• DO NOT prolong testing of fuel injectors or engine may hydrostatically lock.
• On models with 4-speed automatic transaxle, when replacing Transaxle Control Module (TCM), pinion factor and shift quality quick learn procedure should be performed. See PINION FACTOR PROCEDURE and SHIFT QUALITY QUICK LEARN PROCEDURE in the COMPUTER RELEARN PROCEDURES article in the GENERAL INFORMATION section.