TEST 4: Testing For The Presence Of The Activation Signal

Making Sure The Fuel Injection Computer Is Activating The Ignition Coil. How To Test The Coil-On-Plug Ignition Coils (1996, 1997, 1998, 1999 3.2L Isuzu Amigo, Rodeo, Trooper, And Honda Passport)

So far your test results have confirmed that:

  1. You've got an ignition coil that does not fire spark (TEST 1).
  2. This non-sparking ignition coil is receiving 10 to 12 Volts on the BLK/ORG wire.
  3. This non-sparking ignition coil is receiving Ground on the BLK wire.

We're now gonna' make sure that the ignition coil (that's not sparking) is receiving an activation signal from the fuel injection computer.

In this test section we'll check for the activation signal with a multimeter that can read Hertz frequency.

If you don't have a multimeter that can read Hertz frequency, you can check for the activation signal just by swapping coils. You can find this test here: TEST 5: Testing The Activation Signal Without A Multimeter.

Testing for the activation signal should be done with the ignition coil connected to its connector. I recommend using a back probe or a wiring piercing probe to access the signal within the wire. You can see an example of this tool here: Wire-Piercing Probe.

These are the test steps:

  1. 1

    Place the multimeter in Hertz (Hz) mode.

  2. 2

    Reconnect the ignition coil to its electrical connector.

  3. 3

    Probe the activation signal wire with the black multimeter test lead using an appropriate tool to pierce the wire or to back-probe the connector.

    On the 1996-1997 vehicles, this wire connects to the female terminal labeled with the number 2.

    On the 1998-1999 vehicles, this wire connects to the female terminal labeled with the number 1.

  4. 4

    Connect the red multimeter test lead to the battery positive (+) terminal.

  5. 5

    Crank and start the engine.

  6. 6

    You should see fluctuating values of 30 to 60 Hertz as the engine starts and runs on your multimeter.

Let's examine your test result

CASE 1: The multimeter confirmed the presence of the activation signal. This is the correct test result and confirms that the activation signal is present.

You can conclude that this particular non-sparking ignition coil you have just finished testing is bad if you have:

  1. Made sure that it's not sparking (TEST 1).
  2. Made sure that it's getting 10 to 12 Volts (TEST 2).
  3. Made sure that it's getting Ground (TEST 3).
  4. Made sure that it's getting an activation signal (this test section).

If you need to replace the ignition coil, check out my recommendations here: Where To Buy The Ignition Coils And Save.

CASE 2: The multimeter confirmed that the activation signal IS NOT present. Re-check all of your connections and repeat the test again.

If your multimeter still does not report a Hertz reading, then you can conclude that the ignition coil is not receiving an activation signal.

Without an activation signal from the fuel injection computer, the ignition coil will not fire spark.

The most likely cause of this missing activation signal is an open-circuit problem in the wire between the ignition coil's connector and the fuel injection computer's connector.

TEST 5: Testing The Activation Signal Without A Multimeter

Testing The Activation Signal Without A Multimeter. How To Test The Coil-On-Plug Ignition Coils (1996, 1997, 1998, 1999 3.2L Isuzu Amigo, Rodeo, Trooper, And Honda Passport)

If you don't have a multimeter that can read Hertz frequency, then the best way to check for the presence of the ignition coil's activation signal is by simply swapping out the non-sparking ignition coil with a good-sparking ignition coil.

If the good-sparking ignition coil sparks when connected to the non-sparking ignition coil's electrical connector, then you can conclude that the activation signal is present in the connector.

Let's get testing:

  1. 1

    Remove the COP coil that did not spark and set it aside.

  2. 2

    Remove one of the adjacent COP ignition coils that does spark.

  3. 3

    Now connect the COP ignition coil (that sparks) to your HEI spark tester and then connect it to the electrical connector of the COP coil that does not spark.

  4. 4

    When all is ready, have your trusty assistant crank the engine

    .
  5. 5

    The good ignition coil should spark.

Let's interpret you test result:

CASE 1: You got spark. This is the correct test result and confirms that the activation signal is present in the connector of the non-sparking ignition coil.

You can conclude the ignition coil is bad and needs to be replaced if you have:

  1. Made sure that it's not sparking (TEST 1).
  2. Made sure that it's getting 10 to 12 Volts (TEST 2).
  3. Made sure that it's getting Ground (TEST 3).
  4. Made sure that it's getting an activation signal (this test section).

If you need to replace the ignition coil, check out my recommendations here: Where To Buy The Ignition Coils And Save.

CASE 2: You got NO spark. Re-check all of your connections and repeat the test again. If still no spark, then this results eliminates the ignition coil as the source of the NO SPARK condition/misfire, since without the activation signal the ignition coil will not fire spark.