This 'How To Test' article will walk you thru' the entire testing and troubleshooting of the Honda distributor type ignition system that has the ignition coil outside of the distributor.
You'll be able to effectively test and diagnose the igniter (ignition control module -ICM), ignition coil, distributor cap/rotor and spark plug wires with photos and step by step instructions in plain English. Learning how to test this type of Honda ignition system for a misfire condition or a 'no-spark no-start' condition, on your Honda Accord or Prelude, has never been easier!
NOTE: If you need the tests for the Honda distributor ignition system with the ignition coil inside the distributor, click here: How To Test The Accord, Civic and Odyssey Distributor Type Ignition System. For the article to test the Honda Coil-On-Plug ignition coils, go here: How To Test The Coil-On-Plug Ignition Coil 3.0L Honda Accord - Odyssey.
Contents of this tutorial:
- Symptoms Of A Bad Honda Igniter, Ignition Coil, Spark Plug Wires, Or Distributor Cap.
- What Tools Do I Need To Test The Honda Ignition System?
- How Does The 92-01 Honda Accord, Prelude, Igniter (Ignition Control Module) Work?
- Important Do's And Don'ts.
- Safety Precautions And Guidelines When Testing Your Honda.
- TEST 1: Testing For Spark At The Spark Plug Wires.
- TEST 2: Testing For Spark At The Distributor Cap.
- TEST 3: Testing For Spark At The Ignition Coil's High Tension Wire.
- TEST 4: Testing The Ignition Coil For Spark.
- TEST 5: Testing The Ignition Coil & Igniter For Power.
- TEST 6: Testing The Ignition Coil's Switching Signal.
- TEST 7: Testing The Igniter For The Triggering Signal.
- Summary.
You can find this tutorial in Spanish here: Cómo Probar El Módulo y Bobina De Encendido (Accord, Odyssey) (at: autotecnico-online.com).
APPLIES TO: This tutorial applies to the following vehicles:
- Honda Accord 2.2L: 1992, 1993, 1994, 1995.
- Honda Prelude 2.2L: 1992, 1993, 1994, 1995.
NOTE: To test the 1996-1997 2.2L Honda ignition system (with externally mounted ignition coil), see this tutorial: Ignition System Tests (1996-1997 2.2L Accord EX, Odyssey).
NOTE: You might also find the following articles I've written at troubleshootmyvehicle.com useful:
- How To Find A Bad Fuel Injector Case Study (Honda 2.2L, 2.3L) (at: troubleshootmyvehicle.com).
- How To Test For A Bad Fuel Injector (Honda 2.2L, 2.3L) (at: troubleshootmyvehicle.com).
- How To Test Engine Compression (Honda 2.2L, 2.3L) (at: troubleshootmyvehicle.com).
OK, to get started, take a look at all of the info in the next headings since they contain all of the essentials you'll need to know, like: common symptoms, tools needed to perform the tests, do's and don'ts, and a little working theory of how the Honda Accord and Prelude igniter (and by extension the entire ignition system) works.
Symptoms Of A Bad Honda Igniter, Ignition Coil, Spark Plug Wires, Or Distributor Cap
The most common symptom that your Honda Accord or Prelude will experience when the igniter (ignition control module) or the ignition coil goes bad, will be a NO START. In some cases the igniter fails intermittently causing your car to start and run most of the time and not start some of the time.
The most common symptoms when the distributor cap, or spark plug wires go bad is a misfire condition but a no-start condition is also possible. If it runs with a misfire, the misfire will usually light up the check engine light (CEL) on your instrument cluster but not always.
This article will help you to either eliminate or condemn (thru' tests) either the ignition coil or the igniter, or the distributor cap and rotor, or the spark plug wires or the position sensors within the distributor as the cause of the no-start condition or misfire condition. After all, these are the components that fail the majority of the time.
If the igniter is failing intermittently, which would cause your Honda to stall every now and then, you'll have to wait till your Honda does not start to test the ignition system. This is the only way to test for an intermittent problem. If you're experiencing this condition, read this article anyway, you'll be better prepared for when the problem pops up.
What Tools Do I Need To Test The Honda Ignition System?
You don't need any expensive tools to test your Honda ignition system. Here's what you'll need:
- A digital multimeter.
- It doesn't have to be an expensive one, a cheapie one will do just fine.
- A 12 Volt test light.
- An LED light
- I buy mine from Radio Shack since most auto parts stores (Auto Zone, O'Reilly, and the like) sell them for three times as much.
- I've included a link on what this LED light looks like and how to make it into a tool here: The LED Light Test Tool.
- A wire piercing probe.
- To see what this tool looks like, click here: Wire Piercing Probe.
- An HEI spark tester.
- This inexpensive spark tester is a MUST have tool to be able to correctly diagnose your Honda vehicle with the info/tests in this article.
- If you want to learn how the HEI spark tester works, click here: The HEI Spark Tester (The Best Spark Tester On The Market).
- A helper to crank the engine.
And lest I forget, a scan tool is not necessary to diagnose and test the Honda distributor type ignition system. All of the testing that you'll be doing will be done without an automotive diagnostic scanner.
How Does The 92-01 Honda Accord, Prelude,
Igniter (Ignition Control Module) Work?
In a nutshell and when the Honda ignition system is working properly; when you turn the key to crank and start your Honda:
- 12 Volts are fed first to the ignition coil (when you turn the key to ON and then Crank), and from the coil to the igniter (ignition control module) inside of the distributor.
- The distributor shaft starts to turn (as the engine cranks and starts) which induces the position sensors to start producing and sending their position signals to the ECM (Electronic Control Module=Fuel Injection Computer).
- Upon receiving these position signals, the ECM sends a Triggering signal to pulse the igniter.
- The igniter upon receiving this Triggering signal in turn sends a Switching signal to the ignition coil.
- The ignition coil, upon receiving this Switching signal, starts to spark away!
- The Switching signal is just the 'switching' ON and OFF of the primary current flowing thru' the coil by interrupting its path to Ground.
- The primary current is just the name for the 12 Volts that the ignition coil receives.
- The ECM controls the igniter at engine start-up and at all engine speeds after start-up, unlike the majority of distributor-type ignition systems where the ignition control module freelances at engine start-up.
Important Do's And Don'ts
Here are a few suggestions to help you to diagnose your Honda's ignition system free of headaches and/or complications:
- Do not use a regular spark plug instead of a spark tester to test for spark.
- Do not remove the spark plug wire from the spark plug while the engine is cranking to test for spark.
- Keep your hands and fingers away from the rotating distributor shaft when your helper is cranking the engine during the tests.
- Start your diagnostic from TEST 1, do not skip around from test to test.
- Once again, use the recommended/indicated tools for all of your tests.
Safety Precautions And Guidelines When Testing Your Honda
Since you'll be working around a cranking engine this section can be summed up with the following: use common sense and take all necessary safety precautions.
TEST 1: Testing For Spark At The Spark Plug Wires
The purpose of this test is to find out if:
- All of the spark plug wires are NOT firing spark.
- Or if just some (of all) are firing spark.
- From the results of this test, you'll be able to say if the spark plug wires are bad or if you need to dig a little deeper.
Either way, I'll take you step by step thru' the whole process and you'll be able to pinpoint the problem to either a bad igniter (ignition control module), or a bad ignition coil, or bad distributor cap and/or Rotor, or bad spark plug wires. You will also find out if the problem is due to a broken timing belt.
As a side note, you will NOT be testing the resistance of the spark plug wires, since this is the most useless, complete waste of life method to test for bad spark plug wires. The spark plug wire test you're about to do is a dynamic test done with the engine cranking. Read on.
Just a friendly reminder: do not use a regular spark plug instead of a spark tester for the spark test and do not pull the spark plug wire off of the spark plug either while your helper is cranking the engine (to check for spark).
OK, here's the test:
- 1
Remove the spark plug wire from its spark plug.
- 2
Attach the HEI spark tester (or an equivalent spark tester) to the spark plug wire.
- 3
Connect the HEI spark tester to the battery negative (-) terminal with a battery jump start cable.
- 4
Have your helper crank the engine while you observe the spark tester.
- 5
You'll get one of two results: Spark or no spark.
- 6
Repeat the test for all of the remaining spark plug wires.
Let's take a look at what your test results mean:
CASE 1: You got spark on all of the spark plug wires. This is the correct test result and it confirms that the ignition coil and the igniter (ignition control module) are working correctly.
If your Honda Accord or Prelude is suffering a no-start condition, this result indicates that the ignition system is not the cause of it.
If your Honda is suffering a misfire problem, what I recommend you do is an engine compression test or a fuel injector test. You can find these step-by-step tests at troubleshootmyvehicle.com here: How To Test A Misfire Condition (Honda 2.2L, 2.3L).
CASE 2: None of the 4 spark plug wires sparked. Without spark the engine is not going to start.
This could possibly caused by a bad igniter or a bad ignition coil or a bad ignition coil high tension wire.
The cool thing is that these possibilities can be tested. Therefore the next step is to test the high tension cable that connects the ignition coil do the distributor cap. Go to: TEST 3: Testing For Spark At The Ignition Coil's High Tension Wire.
CASE 3: You got spark on some but not all of the spark plug wires. This usually indicates that either the spark plug wires are bad or the distributor cap is bad.
It's a common problem for one or two spark plug wires to go bad or for one or two distributor cap towers to go bad and not let spark thru'. 90% of the time replacing the distributor cap, the distributor rotor and the spark plug wires should solve your problem, BUT to further test this, go to: TEST 2: Testing For Spark At The Distributor Cap.