Preliminary Test PROCECURES

Ignition secondary checks and coil resistance checks are basic system tests required whenever ignition problems are suspected. Cautions are as follows:

• Disconnect battery before disconnecting any ECU wires or connectors.
• Disconnect ignition system while performing a compression check.
• When a spark plug wire is removed from a spark plug, ignition coil or distributor cap, silicone grease must be applied to boot before it is reconnected.
• On vehicles with a catalytic converter, do not run engine for more than 30 seconds with a spark plug wire removed.
• When checking continuity or voltages, ensure all connections are tight and free of corrosion. If poor connections exist, incorrect readings may be obtained.
• When disconnecting ECU connectors, pull apart with a firm, straight pull. Do not use screwdrivers to pry connectors apart. When connecting them, press together firmly to ensure complete contact is achieved.
• When removing spark plug wires, grasp boot only and twist, pulling boot off with steady even force.
• Turn ignition switch to "OFF" position when connecting test equipment or when replacing parts.
• When conducting tests, do not short out high tension current on ICM housing. Do not ground ignition coil low tension or high tension windings, or the primary terminals.