What is an ICM on a car?
What exactly is an (ICM) Ignition Control Module? An ICM is nothing more than a switch that turns the ignition system “On” or “Off”. Inside of the distributor there is a sensor that sends out a signal to the ICM, which is then used to fire up the ignition coil that will create enough energy for the spark plugs.
What happens when the ICM fails on a GM car?
Generally, when the ICM or the ignition coil fails, your GM car or truck will Crank but NOT START. Specifically, the ignition coil will not spark.
How does the Ignition Control Module ( ICM ) work?
If everything is working properly, the engine will start. Now, the important thing to know is that the PCM controls the creation of spark from the get-go (crank up) and at all engine speeds thru’ the ignition control module (ICM).
What happens when the ignition coil does not work?
NOTE: When the ignition coil or the ICM start to fail, they don’t always cause a cranks but does NOT start condition, since sometimes these components can fail intermittently. In this scenario, your vehicle will start and run most of the time, but every now and then it won’t.
How many wires does the ignition module have?
The ignition control module (ICM) has 4 wires coming out of it. Below are the descriptions of what each circuit does. Each circuit is identified by a letter, and this is the same letter that you will find on the ignition module’s connector.
What happens if there is no external signal to the ignition coil?
With no external signal to the coil negative primary post, voltage would travel through the ignition coil windings without inducing any secondary spark. A switch, or signaling device, triggers an interruption in the circuit.
Generally, when the ICM or the ignition coil fails, your GM car or truck will Crank but NOT START. Specifically, the ignition coil will not spark.
If everything is working properly, the engine will start. Now, the important thing to know is that the PCM controls the creation of spark from the get-go (crank up) and at all engine speeds thru’ the ignition control module (ICM).
Where does the power from the ignition coil come from?
Each circuit is identified by a letter, and this is the same letter that you will find on the ignition coil’s connector. Power (12 V) Circuit. Tach Signal for the tachometer in the instrument cluster if equipped. Switching Signal Circuit. This wire (circuit) comes from the ignition module.