This tutorial will help you diagnose a bad ignition coil that's causing your 2.4L Nissan D21 pickup from starting.
Everything is explained in plain English and in a step-by-step manner so that you can find out if the ignition coil is defective or not.
Contents of this tutorial:
- Ignition Coil Circuit Descriptions.
- Making Sure Spark Is Missing At All Spark Plug Wires.
- Where To Buy The Ignition Coil.
- TEST 1: Testing Ignition Coil's High Tension Wire For Spark.
- TEST 2: Testing For Spark Directly On The Ignition Coil Tower.
- TEST 3: Making Sure The Ignition Coil Is Getting Power.
- TEST 4: Making Sure The Power Transistor Is Activating The Ignition Coil.
- More 2.4L Nissan Tutorials.
You can find this tutorial in Spanish here: Cómo Probar La Bobina De Encendido (1992-1994 2.4L Nissan D21 Pickup) (at: autotecnico-online.com).
The following tutorials complement this one:
- How To Test The Power Transistor 1992-1994 Nissan D21 Pickup.
- How To Test The Crank Angle Sensor (1990-1996 2.4L Nissan Pickup).
- 1992-1994 2.4L Nissan D21 Pickup Ignition System Wiring Diagram.
Ignition Coil Circuit Descriptions
The ignition coil, on the 1992, 1993, and 1994 2.4L Nissan D21 Pickup has 2 wires coming out of its engine wiring harness connector.
Below is a brief description of each:
NOTE: Checkout the 1992-1994 2.4L Nissan D21 ignition system wiring diagram here: 1992-1994 2.4L Nissan D21 Pickup Ignition System Wiring Diagram.
Here's a brief description of each terminal:
| 1992-1994 D21 Ignition Coil Connector | ||
|---|---|---|
| Pin | Wire Color | Description |
| 1 | Blue | IGC -Ignition coil control signal |
| 2 | Black with white stripe | Power -Battery power |
Making Sure Spark Is Missing At All Spark Plug Wires
Before you start with the tests in this tutorial, you need check all 4 spark plug wires for spark. This step is super important!
If even one spark plug wire is sparking, then you can conclude that the ignition coil is functioning and by extension, that the power transistor (ignition control module) is working too.
So, if you have tested for spark and none of the spark plug wires are sparking, then proceed. If not, check for spark first.
One more thing: I recommend using a dedicated spark tester for all of your tests. This will ensure an accurate test result. I recommend using an HEI spark tester. This bad boy is not expensive and very, very accurate! You can find out where to buy it here: The HEI Spark Tester.
Where To Buy The Ignition Coil
Yup, this bad boy isn't expensive. Check out the following links and comparison shop:
TEST 1: Testing Ignition Coil's High Tension Wire For Spark
To get our ignition coil diagnostic started, we're gonna' test the ignition coil's high tension wire for spark.
It's not uncommon for the ignition coil's high tension wire to fail. When it fails, it'll stop transmitting spark from the ignition coil to the distributor cap.
To connect the spark tester to the high tension wire's metal terminal, you'll need to use a piece of black electrical tape to join them together.
In the illustration above, the larger orange arrow points to the spot you'll need to use the black electrical tape to join the terminals.
These are the test steps:
- 1
Disconnect the high tension wire that connects to the middle tower of the distributor cap. Leave the other end of the high tension wire connected to the ignition coil.
NOTE: This is the high tension wire that connects the ignition coil to the distributor cap. - 2
Connect the spark tester to the high tension wire.
IMPORTANT: You'll need to use a small piece of black electrical tape to connect the spark tester to the metal terminal of the high tension wire. - 3
Ground the spark tester, using a battery jump start cable, to the battery negative (-) post.
- 4
Have your helper crank the engine as you hold the spark tester with the battery jump start cable.
- 5
The spark tester should spark as the engine turns.
Let's examine the result of your spark test:
CASE 1: The spark tester sparked. This is the correct and expected test result and tells you that your Nissan D21's the high tension wire and the ignition coil are good.
If you have no spark coming out of the 4 spark plug wires, then you can correctly conclude that the distributor cap and rotor are defective and behind your Nissan D21's 'no-spark no-start' problem and they need to be replaced.
CASE 2: The spark tester DID NOT spark. The next step is to test for spark directly on the ignition coil's tower. For this test, go to: TEST 2: Testing For Spark Directly On The Ignition Coil Tower.