How To Test The Ignition System (1992-1997 3.9L Dodge Dakota)

TEST 4: Testing The Ignition Coil For Spark

If you've reached this point, your tests have confirmed that:

• None of the six spark plugs have spark (TEST 1).
• The ignition coil's high tension wire is not sparking (TEST 3).

We're now gonna' test for spark directly on the ignition coil's tower. If the spark tester sparks, then you can conclude that the ignition coil's high tension wire is bad and that this is the reason you got no spark at all six spark plug cables.

If the spark tester does not spark, then the next test is to make sure that the ignition coil is getting power (in TEST 5).

These are the test steps:

1. 1

   Disconnect the high tension wire that connects to the ignition coil.

2. 2

   Connect the spark tester to the ignition coil's tower with a small piece of vacuum hose (see photo above).

3. 3

   Ground the spark tester directly on the battery negative (-) terminal with a jump start cable.

4. 4

   Have your helper crank the engine.

5. 5

   The spark tester should spark.

Let's examine your test result:

CASE 1: The spark tester sparked. This is the correct test result.

This test result lets you know that the ignition coil is good. You can also conclude that the ignition coil's high tension wire is bad if you have:

• Confirmed that none of the spark plug wires have spark in TEST 1.
• Confirmed that the ignition coil's high tension wire did not spark in TEST 3.
• Confirmed in this test section that the ignition coil does spark.

CASE 2: The spark tester DID NOT spark. The next test is to make sure that the ignition coil is getting 10 to 12 Volts.

For this test go to: TEST 5: Making Sure The Ignition Coil Is Getting 12 Volts.

TEST 5: Making Sure The Ignition Coil Is Getting 12 Volts

Since you got a no-spark test result in TEST 4, the next step is to make sure that the ignition coil is getting 10 to 12 Volts.

The wire that feeds these 10 to 12 Volts is the dark green with orange stripe (DK GRN/ORG) wire of its 2-wire connector. In the photo above, this wire is labeled with the number 2.

We can easily test the presence of this 10 to 12 Volts on the DK GRN/ORG wire by doing a simple multimeter voltage test.

CAUTION: To check for the presence of 12 Volts you must crank the engine. Be careful and take all necessary safety precautions!

These are the test steps:

1. 1

   Select Volts DC mode on your multimeter.

2. 2

   Disconnect the ignition coil from its electrical connector.

3. 3

   Connect the red multimeter test lead to the DK GRN/ORG wire.

4. 4

   Connect the black lead of the multimeter to the battery (-) negative terminal.

5. 5

   Have your helper crank the engine while you observe the multimeter.

6. 6

   You should see 10 to 12 Volts on the multimeter.

Let's analyze your test result:

CASE 1: 10 to 12 Volts are present in the DK GRN/ORG wire. This is the correct test result and it tells you that the ignition coil is getting power.

Since your Dodge Dakota's ignition coil does not fire spark, the next step is to check that the ignition coil is receiving an activation signal. Go to: TEST 6: Testing The Ignition Coil's Activation Signal.

CASE 2: 10 to 12 Volts ARE NOT present in the DK GRN/ORG wire. Without power the ignition coil will not fire spark.

This lack of spark will be caused by one of the following:

• An open-circuit problem in the DK GRN/ORG wire between the ignition coil's connector and the ASD relay.