Is there a spark in the ignition module?

There is no spark coming out of any of the ignition coils sitting on top of the ignition module. You may have taken your ignition control module (ICM) to Auto Zone to test it and the friendly boys in orange say it’s good, yet the vehicle will not start (all major auto parts stores such as O’Reilly, Pepboys, etc., test ignition modules for free).

How does the ignition control module work in a car?

Basic Theory: How The Ignition Control Module Works. In a nutshell, the ignition control module’s job is to create a Switching signal for the ignition coils that are sitting on top of it. It’s this Switching signal that makes the ignition coils create spark.

How to test the ignition module and crank sensor?

So, if you’re driving a Chevy, a Buick, a Pontiac, or an Oldsmobile with either one of these engines, not forgetting the Isuzu Rodeo or Trooper, this ‘How To Test The Ignition Module’ and 7X (3X) article applies. There are two other articles that may help:

What kind of tool do you need to test ignition module?

The most important tool to have is a multimeter. It can be a digital or analog type. You do not need an automotive scan tool. Here are the other recommended tools that will come in handy. Test light. You can use the test light instead of a multimeter to test for 12 Volts, only. Wire piercing probes.

What is the crank sensor on a GM 3.1L engine?

This article will help you test the ignition control module (ICM) and 3X crankshaft position sensor on all of the GM 3.1L and 3.4L overhead valve engines (the 3X crank sensor is also known as the 7X Crank Sensor).

How to know if your engine has no spark?

First Confirm Your Engine Has No Spark. 1 Disable the fuel system by removing the fuel pump fuse or relay. 2 Insert a spark plug tester into the plug boot and ground it on a piece of metal on the engine. 3 Finally, Have someone crank the engine and watch for spark.

What causes a crank sensor to not start?

Now, if the NO START is caused by the ignition module or the crank sensor, usually the ignition coils will not fire any spark at all. Therefore, the second symptom that leads you on the path of a BAD ICM or crank sensor is: No spark at any of the ignition coils.

What kind of signal does the ignition module need?

OK, moving on along… for the ignition module to create this Switching signal, it needs to receive a C ran k shaft P osition (CKP) sensor signal (this signal is usually referred to as the Triggering signal and in GM service literature it’s known as the 3X or 7X CKP signal).

What are the symptoms of an ignition failure?

Here are some of the most common failure symptoms: The car (or minivan or Isuzu SUV) cranks but does not start. There is no spark coming out of any of the ignition coils sitting on top of the ignition module.

When does the ignition coil start to spark?

The action of switching ON and OFF the primary voltage (ignition coil’s battery power) is referred to as the switching signal. Once the ignition coil gets this switching signal, it starts to spark away and as you’re already aware, this spark gets delivered to the center of the distributor cap by a high tension wire.

How is the spark plug fed to the distributor?

This opening and closing action is referred to as the Switching Signal in this article. The spark created by the ignition coil is fed to the distributor cap by a high tension wire and from there to each engine cylinder by a spark plug wire.

How to troubleshoot a no start ignition coil?

How To Troubleshoot A No Start (Ford 4.9L, 5.0L, 5.8L). This may seem like a no brainer because the most obvious symptom of a bad ignition coil is a no start no spark condition, but here are a few other symptoms you’ll see along with no spark:

Why does my GM 3.8L have no spark?

Here are the most common causes of a no-spark result: CASE 1: Spark was present in all of the cylinders This result tells you three very important things: 1.) the crank sensor is good, 2.) the ignition control module is OK, and 3.) the ignition coil coil packs are good. You don’t have to spend any time testing them or any money replacing them.

How to troubleshoot a GM 3.8L no start?

It’s been my experience that the majority of the Cranks but Does no start conditions I’ve troubleshooted and repaired (on GM 3.8L equipped vehicles) had their root cause in the ignition system. So, my recommendation to you is to check for spark at all of the spark plug wires with a spark tester.

What makes an engine not start or run?

All engines require three things to start and run: spark, fuel and compression. If any one of these is missing, your engine will not start. The fuel pump is running and delivering normal pressure to the engine