TEST 2: Making Sure The Ignition Coil Is Getting 12 Volts
OK, so far TEST 1 has confirmed that one or more of the ignition coils are not firing spark.
The next step is to verify that that ignition coil or coils (that did not spark) are receiving 10 to 12 Volts DC.
On the 1996-1997 vehicles, the wire that we're gonna' test is the wire that connects to the female terminal labeled with the number 1 in the photo above.
On the 1998-1999 vehicles, the wire that we're gonna' test is the wire that connects to the female terminal labeled with the number 2 in the photo above.
On all vehicles (1996-1999), this wire is the black with orange stripe (BLK/ORG) wire of the ignition coil's electrical connector.
We'll check for the presence of this voltage with a multimeter voltage test.
NOTE: Be careful when probing the front of the female terminal of the ignition coil's connector to avoid damaging it.
OK, let's get started:
- 1
Disconnect the ignition coil from its electrical connector.
- 2
Put the multimeter in Volts DC mode.
- 3
Probe the BLK/ORG wire of the ignition coil's connector with the red multimeter test lead (using an appropriate tool).
On the 1996-1997 vehicles, this wire connects to the female terminal labeled with the number 1.
On the 1998-1999 vehicles, this wire connects to the female terminal labeled with the number 2. - 4
Connect the black multimeter test lead to the battery negative (-) terminal.
- 5
Have your helper turn the key to the ON position.
- 6
You should see 10-12 Volts on your multimeter.
Let's take a look at what your test results mean:
CASE 1: The multimeter registered 10-12 Volts. This is the correct test result and lets you know that the ignition coil is getting power.
The next step is to make sure the ignition coil is getting Ground. Go to: TEST 3: Making Sure The Ignition Coil Is Getting Ground.
CASE 2: The multimeter DID NOT register 10-12 Volts. This tells you that the ignition coil is not getting power and without it, the ignition coil will not spark.
This test result eliminates the COP ignition coil itself as bad and as the source of the misfire condition.
Since the power circuit is shared by all of the COP ignition coils, the most likely cause of this missing voltage is a bad ignition coil connector or an open-circuit problem in the wire between the connector and the engine wiring harness.
TEST 3: Making Sure The Ignition Coil Is Getting Ground
So far you have confirmed that the ignition coil that is not firing off spark is getting 10 to 12 Volts DC on the BLK/ORG wire.
The next step is to verify that that ignition coil is getting Ground.
On all vehicles (1996-1999), this wire is the black (BLK) wire and connects to the female terminal labeled with the number 3 of the ignition coil's electrical connector.
We'll check for the presence of this Ground by doing a multimeter voltage test.
NOTE: Be careful when probing the front of the female terminal of the ignition coil's connector to avoid damaging it.
These are the test steps:
- 1
Disconnect the ignition coil from its electrical connector.
- 2
Put the multimeter in Volts DC mode.
- 3
Probe the BLK wire with the black multimeter test lead (using an appropriate tool).
On all vehicles (1996-1999), this wire connects to the female terminal labeled with the number 3 in the photo above. - 4
Connect the red multimeter test lead to the battery positive (+) terminal.
- 5
Have your helper turn the key to the ON position.
- 6
You should see 10-12 Volts on your multimeter
If you're using a 12 Volt test light, the test light should light up.
Let's examine your test result:
CASE 1: The multimeter registered 10-12 Volts. This is the correct test result and confirms that the ignition coil is getting Ground.
The next step is to verify that the ignition coil is receiving a activation signal, go to: TEST 4: Testing For The Presence Of The Activation Signal.
CASE 2: The multimeter DID NOT register 10-12 Volts. This test results tells you that the ignition coil is not getting Ground and without it, the ignition coil will not spark.
This test result eliminates the COP ignition coil itself as bad and as the source of the misfire condition.
Since the Ground circuit is shared by all of the COP ignition coils, the most likely cause of this Ground is a bad ignition coil connector or an open-circuit problem in the wire between the connector and the engine wiring harness.
TEST 4: Testing For The Presence Of The Activation Signal
So far your test results have confirmed that:
- You've got an ignition coil that does not fire spark (TEST 1).
- This non-sparking ignition coil is receiving 10 to 12 Volts on the BLK/ORG wire.
- 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
Place the multimeter in Hertz (Hz) mode.
- 2
Reconnect the ignition coil to its electrical connector.
- 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
Connect the red multimeter test lead to the battery positive (+) terminal.
- 5
Crank and start the engine.
- 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:
- Made sure that it's not sparking (TEST 1).
- Made sure that it's getting 10 to 12 Volts (TEST 2).
- Made sure that it's getting Ground (TEST 3).
- 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.
