How to Replace an Ignition Module

by Paul Vaughn

Your ignition module is, very simply, an electronic switch. This switch times the firing of the spark plugs with the rotation of the pistons. Without this switch, the engine will either not run at all or backfire into the exhaust or intake manifolds causing piston and valve damage. This article will explain how to replace an ignition module.

Replacing and testing the ignition module.

Use your flat tip screwdriver to gentle push the holding clamps away from the connecting plug that plugs into the ignition module. Take care not to put too much pressure on the holding clamps as this will cause them to break requiring replacement of the connector.

Gently pull the connecting plug away from the plug end in your ignition module. Move the connector and any wires surrounding the ignition module away from the module to prevent damaging them when removing the module.

Use your Phillips screwdriver to loosen the mount screws by turning them counter clockwise. Remove the screws by hand and set them aside.

Gently lift the ignition module out from its mounting surface and set aside. Place your new module on the mounting surface and install the mounting screws using your Phillips screwdriver turning them clockwise until snug. Do not over tighten these screws as it will damage the threads and make tightening impossible.

Plug the wire connector into the socket on your ignition module. Make sure it is seated properly and plugged in all the way. A loose connector can cause the model to operated erratically. With your ignition key turned to the "On" position, use the DVOM to check for voltage to and from the connector. Connect your test light to the negative side of the ignition coil and turn over the engine. If the test light goes on and off, the ignition module is properly installed.


  • check Take care not to cross any wires or damage them during the installation process
  • check Take care not to over tighten mounting screws so as not to damage the threads
  • check When plugging in the connector to the ignition module, make sure it fits easily into the socket. If it is difficult to plug in, check the position of the plug and adjust accordingly


  • close Do not cross the battery terminals during installation. This will cause shock injuries.

Items you will need

About the Author

Paul Vaughn has worked in the auto and diesel mechanics field for 10 years and as public school automotive vocational teacher for five years. He currently teaches high school auto tech, covering year model vehicles as old as 1980 to as new as 2007.

More Articles