How To Test The Ignition Coil (1993-1995 2.5L SOHC Dodge Dakota)

TEST 2: Making Sure The Ignition Coil Is Getting Power

If you've reached this point, then the ignition coil did not spark in TEST 1. Our next step is to make sure that your Dodge Dakota's ignition coil is getting power.

This power comes in the form of battery voltage and is fed to the ignition coil wire via the dark green with orange stripe (DK GRN/ORG) wire of the ignition coil's connector.

To check for this battery voltage, we're going to do a simple multimeter voltage test.

If battery voltage is present in the DK GRN/ORG wire, then our next step is to test the ignition coil's activation signal while cranking the engine (TEST 3).

Let's get started:

1. 1

   Disconnect the 2-wire distributor connector.

2. 2

   Connect the red multimeter test lead to the DK GRN/ORG wire of the ignition coil connector.
   
   NOTE: Don't probe the front of the connector, or you'll damage the female terminal. Use a back probe or a wire piercing probe to check for battery power.

3. 3

   Connect the black multimeter test lead to the battery (-) negative post.
   
   Have your helper turn the key to the ON position.

4. 4

   Your multimeter should read 10 to 12 Volts DC if the ignition coil is getting battery power.

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

CASE 1: The ignition coil is getting 10 to 12 Volts DC. This is the correct and expected test result.

The next step is to make sure that your Dodge Dakota's fuel injection computer is activating the ignition coil. For this step, go to: TEST 3: Checking For The Ignition Coil Control Signal.

CASE 2: The ignition coil IS NOT getting battery power. This tells you that the ignition coil is not working due to a lack of battery power.

Your next step is to find out why this battery power is missing and restore it. Once battery power is restored, the ignition coil should function again.

TEST 3: Checking For The Ignition Coil Control Signal

In this last test section, we're gonna' see if your 2.5L Dodge Dakota's fuel injection computer is activating the ignition coil (or not).

Yup, this means that your Dodge Dakota's ignition system does not use an externally mounted ignition control module (since this function is part of the fuel injection computer itself).

This is a very simple test but to test for the coil's activation signal requires that you use an LED light with a built in resistor.

You can see an example of the LED light that you need to use here: The LED Light Test Tool and How To Make One.

NOTE: LEDs are polarity specific and so their wires will be black and red. This also means that you'll need to pay close attention to what the instructions are telling you to connect the black or red LED wires.

Here are the test steps:

1. 1

   Disconnect the ignition coil from its connector.

2. 2

   Connect red LED wire to the DK GRN/ORG wire of the ignition coil's wiring harness connector. This is the power circuit of the ignition coil.

3. 3

   Connect black LED wire to the grey (GRY) wire of the ignition coil's wiring harness connector. This is the activation signal circuit of the ignition coil.

4. 4

   Have your helper crank the engine after the LED light is set up.

5. 5

   The LED light should flash ON and OFF as the engine turns if the ignition coil control signal is present.

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

CASE 1: The LED light flashed ON and OFF as the engine was cranked. This is the correct and expected test result and confirms that your 2.5L Dodge Dakota's fuel injection computer is activating the ignition coil.

You can now conclude that the ignition coil is defective and needs to be replace if you have:

• Confirmed a lack of spark at all 4 cylinders.
• Confirmed no spark directly on the ignition coil tower (TEST 1).
• Confirmed the ignition coil is getting power (TEST 2).
• Confirmed the ignition coil is getting an activation signal from the fuel injection computer.

CASE 2: The LED light DID NOT flash ON and OFF as the engine was cranked. This tells you that the fuel injection computer is not sending an ignition coil control signal.

This missing ignition coil control signal is usually due to a defective distributor pick-up coil. Although it's beyond the scope of this tutorial to test it, you have eliminated your 2.5L Dodge Dakota's ignition coil as defective (since without its activation signal, it won't spark).

Testing the distributor pick-up coil can easily be done with a multimeter. You can find the test here: How To Test The Distributor Pick-Up Coil (1990-1995 2.5L SOHC Dodge Dakota).

More 2.5L Dodge Dakota Tutorials

You can find a complete list of tutorials here: Chrysler 2.5L 4-Cylinder Index Of Articles.

Here's a sample of the tutorials you'll find there:

• Oxygen Sensor Heater Test (1993-1995 2.5L Dodge Dakota).
• How To Test The TPS (1993-1995 2.5L SOHC Dodge Dakota).
• How To Test The MAP Sensor (1994-1995 2.5L SOHC Dodge Dakota).
• How To Test Engine Compression (1993-2002 2.5L Dodge Dakota).