TEST 3: Testing For Spark At The Ignition Coil Pack
This step test is for when two spark plug wires that are connected to paired cylinders (either paired cylinders #1 and #4 or paired cylinders #2 and #3) did not fire spark.
You're gonna' test one ignition coil tower at a time. So pick one to test first and then test the second one.
The best and safest way to accomplish this is by Grounding the spark tester with a battery jump start cable to the battery's negative (-) terminal.
These are the test steps:
Remove one of the spark plug wires that did not fire off spark from the ignition coil pack.
Place the spark tester directly on the ignition coil tower in place of the spark plug wire you just removed (see photo above).
Connect the spark tester to the battery negative (-) terminal with a battery jump start cable.
Have your helper crank the engine.
You're gonna' get one of two results: spark or NO spark.
Repeat tests 1 thru' 5 on the other ignition coil tower whose spark plug wire did not fire off spark.
Let's take a look at what your test result means:
CASE 1: You got spark from only one tower. This result lets you know that the ignition coil is bad. Replace the ignition coil.
CASE 2 If you got spark from both towers. This result lets you know that the ignition coil is good and that the spark plug wires are bad. Replace all of the spark plug wires as a set.
CASE 3: You got NO spark from both towers. The next step is to test for the Switching signal.
If you got no spark from the towers that feed spark to cylinders 1 and 4 go to: TEST 5.
If you got no spark from the towers that feed spark to cylinders 2 and 3 go to: TEST 6.
TEST 4: Testing The Power (12 Volts) Circuit
Testing the power circuit of the Ford coil pack can be done with a 12 Volt test light or a multimeter.
The wire that feeds power to the ignition coil is the middle wire of the coil pack connector. This wire is labeled with the number 2 in the photos above.
Also, it can be done with the coil pack connected or not to its connector. The following test steps assume that you'll test the power circuit with a multimeter and with the connector connected to the ignition coil pack.
Remove enough of the black electrical tape that's wrapped around the 3 wires of the connector to expose them for testing.
Disconnect the ignition coil from its connector.
Put the multimeter in Volts DC mode.
Probe the wire labeled with the number 2 with the red multimeter test lead (using an appropriate tool).
Connect the black multimeter test lead to the battery negative (-) terminal.
Have your helper turn the key to the ON position.
You should see 10-12 Volts on your multimeter.
Let's find out what your test result means:
CASE 1: The multimeter registered 10 to 12 Volts DC. This is the correct test result.
Then the next step is verify that the Switching signals are present, go to: TEST 5 and then perform TEST 6.
If the both Switching signals are not present (after testing them in TEST 5 and TEST 6), the most likely cause will be that the crankshaft position sensor is bad.
- If you need the test the crankshaft position sensor, I've written a tutorial that'll help you here: How To Test The Crankshaft Position Sensor (Ford 1.9L, 2.0L) (at: troubleshootmyvehicle.com).
CASE 2: The multimeter DID NOT register 10 to 12 Volts DC. Re-check all of your connections and retest.
If still no voltage is present, this result exonerates the coil pack. Repairing the cause of this missing voltage will solve the 'no-spark no-start' condition of your Ford (or Mercury or Mazda) car.