Ignition Coil Test -No Spark No Start Tests
(Ford 4.9L, 5.0L, 5.8L)

IGNITION COIL TEST 3:
Verifying Ignition Coil is Getting 12 Volts

So far, you have verified that you do have a bona-fide no spark situation coming directly from the ignition coil because:

One: Your Ford's no start condition is due to a lack of spark (and nothing else).

Two: You have eliminated the ignition coil's high tension wire as bad (TEST 2).

The next test is to make sure the ignition coil is getting battery power either using a multimeter or a 12 V DC test light.

Alright, this is what you'll need to do:

  1. 1

    With your multimeter still in volts DC mode from the previous test and the Key On (but engine Off).

  2. 2

    Probe the wire labeled with the number 2 in the image viewer, with the RED multimeter lead.

  3. 3

    Now ground the multimeter's BLACK test lead on the battery's negative (-) Post.

  4. 4

    Your multimeter should show you either: 1.) 12 volts DC or 2.) 0 volts.

Let's take a look at what your results mean:

CASE 1: The multimeter registered 12 volts. This is the correct result and tells you that the next step is to check that the ignition coil is getting a switching signal from the ignition control module (ICM). Go to IGNITION COIL TEST 4: Verifying the Switching Signal With a Test Light.

CASE 2: The multimeter DID NOT register 12 volts. Double check your multimeter connections and repeat the test... if your multimeter results still do not indicate 12 volts, then the ignition coil is not fried and not the cause of the no spark no start problem, since without power, it won't work.

Although it's beyond the scope of this article to find the cause of these missing 12 volts, resolving this issue will solve the no spark no start issue.

IGNITION COIL TEST 4:
Verifying the Switching Signal With a Test Light

In the previous test you confirmed that the ignition coil is being supplied with power (12 volts DC).

Now, you need to see if the ignition coil is getting an activation signal, called the switching signal, from the ignition control module (ICM).

This test is accomplished using a 12 volt test light and is done while cranking the engine on your 4.9L, 5.0L, or 5.8L Ford pick up (or car or SUV).

Alright, this is what you'll need to do:

  1. 1

    Reconnect the high tension wire to the ignition coil and the distributor cap, if you haven't done so.

  2. 2

    Probe the wire labeled with the number 1 in the image viewer with the test light's metal probe and.

    Connect the test light's crocodile type connector to your Ford's battery positive post.

    The ignition coil can be connected to its electrical connector or not.

  3. 3

    When ready, have your helper crank the engine while you observe and hold the test light in place.

  4. 4

    Your 12 volt test light will either:

    1.) Flash On and Off the whole time the engine is cranking.

    2.) No flashing On or Off.

Let's take a look at what your results mean:

CASE 1: The test light flashed On and Off. This is means that the ignition control module is activating the ignition coil and since the ignition coil is not sparking... the ignition coil is BAD. Replace the ignition coil.

Here's why: If the ignition coil is getting power (12 volts) and is getting the switching signal, it HAS TO SPARK, since it isn't, this tells you that it's fried.

If you'd like to save a few bucks buying the ignition coil (and factory original Motorcraft ignition components), take a look at the following section: Where to Buy the Ignition Coil and Save.

CASE 2: The test light DID NOT flash On and Off. This test result exonerates the ignition coil, since without this switching signal, it won't spark.

The most likely cause of this missing switching signal is either a BAD ignition control module (ICM) or a BAD profile ignition pickup (PIP) sensor (which is Ford's fancy name for the crank sensor). I have written an article that will help you to test both of these at:

1.) If your Ford vehicle has the ignition control module mounted on the Distributor, go to: Ford Distributor Mounted Ignition Module and PIP Sensor Test (this article is found at easyautodiagnostics.com).

2.) If your Ford vehicle has the ignition control module mounted on the Fender, go to: Ford Fender Mounted Ignition Module and PIP Sensor Test (this article is found at easyautodiagnostics.com).

Ford Vehicles:

  • Bronco 4.9L, 5.0L, 5.8L
    • 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996
  • Crown Victoria 5.0L
    • 1989, 1990, 1991
  • E150, E250, E350 4.9L, 5.0L, 5.8L
    • 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996

Ford Vehicles:

  • F150, F250, F350 4.9L, 5.0L, 5.8L
    • 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997
  • Mustang 5.0L
    • 1988, 1989, 1990, 1991, 1992, 1993
  • Thunderbird 5.0L
    • 1988, 1989, 1990

Lincoln Vehicles:

  • Continental
    • 1988, 1989, 1990
  • Mark VII
    • 1988, 1989, 1990, 1991, 1992
  • Town Car
    • 1988, 1989, 1990

Mercury Vehicles:

  • Cougar 5.0L
    • 1988, 1989, 1990

Mercury Vehicles:

  • Grand Marquis 5.0L
    • 1988, 1989, 1990, 1991

“I am not afraid of death, I just don’t want to be there when it happens.”
Woody Allen

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