TEST 4: Testing For Spark At The Ignition Coil Pack (Paired Cylinders)
NOTE: This test section applies when two spark plug wires from paired cylinders (#1 and #4, or #2 and #3) did not fire spark.
What we're gonna do is check for spark directly at the coil pack towers of those non-sparking wires with our spark tester.
You'll get one of two results:
- The tower sparks: This means its spark plug wire is bad and that's why it didn't spark in TEST 1.
- The tower doesn't spark: This means the ignition coil pack is bad and that's why the wire didn't spark in TEST 1.
These are the test steps:
- 1
Remove the spark plug wire that did not spark from the coil pack.
- 2
Place the spark tester directly on the coil pack tower for that wire (see the example in the photo above).
- 3
Connect the spark tester to the battery negative (-) terminal using a battery jump start cable.
- 4
Have your helper crank the engine.
CAUTION: The engine may start, so be careful. - 5
You'll see one of two results: Spark or NO spark.
- 6
Remove the spark tester and reconnect the wire to its coil pack tower.
- 7
Repeat the same spark test on the other coil pack tower —the one that connects to the second non-sparking wire you identified in TEST 1.
Let's take a look at what your test result means:
CASE 1: You got spark from only one tower. This result tells you two things:
- The ignition coil pack is bad —since it's only sparking from one tower.
- The spark plug wire is bad —the one that connects to the sparking tower, since it didn't spark in TEST 1.
Replace the coil pack and spark plug wires to solve your Ford Escape or Mazda Tribute's no-start problem.
CASE 2: You got spark from both towers. This means the coil pack is OK and doing its job —the spark plug wires are bad, since they didn't spark in TEST 1.
Replace all of the spark plug wires as a set.
CASE 3: You got NO spark from both towers. Your next step is to test for the ignition coil activation signal.
If there's no spark from the towers that supply spark to cylinders 1 and 4, go to: TEST 6: Checking The Activation Signal For Coil A (Cylinders 1 & 4).
If there's no spark from the towers that supply spark to cylinders 2 and 3, go to: TEST 7: Checking The Activation Signal For Coil B (Cylinders 2 & 3).
TEST 5: Making Sure The Coil Pack Is Getting IGN 12 Volts
In this test section, we're going to make sure the ignition coil pack is getting 12 Volts (IGN).
These 12 Volts are only present when the key is in the RUN or START position, and are delivered by the white with violet stripe (WHT/VIO) wire.
To check for this IGN 12-Volt supply, we'll do a multimeter test at female terminal 2 of the coil pack connector —the terminal the WHT/VIO wire connects to.
NOTE: You'll be probing the front of the ignition coil connector. Take care not to damage the female terminal with your multimeter test leads, or you'll end up having to replace the connector.
Let's start:
- 1
Disconnect the coil pack from its connector.
- 2
Turn the key to the RUN position but don't crank the engine.
- 3
Put the multimeter in Volts DC mode.
- 4
Connect the black multimeter test lead to the battery negative (-) terminal.
- 5
Gently probe the front of terminal 2 with the red multimeter test lead.
- 6
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. Good —this is the result we wanted to see and it confirms the coil pack is getting IGN power.
The next step is to make sure the coil pack is receiving both of its coil A and B activation signals. For this test, go to: TEST 8: Checking Coil A And B Activation Signals.
CASE 2: The multimeter DID NOT register 10 to 12 Volts DC. Double-check your multimeter connections and repeat the test.
If you still don't see IGN 12V at terminal 2, then the coil pack itself isn't causing your Ford Escape or Mazda Tribute's no-start problem. Without IGN power, the coil pack can't function.
Your next step is to troubleshoot why the WHT/VIO wire isn't delivering 12V to the coil pack. Once this voltage is restored, the coil pack should fire spark to all four cylinders.
TEST 6: Checking The Activation Signal For Coil A (Cylinders 1 & 4)
Up to this point, you've confirmed two things:
- Spark plug wires for cylinders 1 and 4 aren't sparking (TEST 1).
- The coil pack towers for those same wires aren't sparking either (TEST 4).
In this section, we're going to check if the ignition coil A (within the coil pack), which supplies spark to cylinders 1 and 4, is receiving its activation signal.
This signal is delivered by the dark green with violet stripe (DK GRN/VIO) wire at terminal 1 of the coil pack's 3-wire connector.
We'll use a 12-Volt test light to confirm the presence of coil A's activation signal at terminal 1.
NOTE: Use a regular 12-Volt test light with an incandescent bulb to check for the coil's activation signal. If you don't have one, this is the one I recommend —you can buy it here: Lisle 28400 Heavy Duty 12 Volt Test Light (Amazon affiliate link).
Alright, let's start:
- 1
Disconnect the coil pack's 3-wire connector.
- 2
Clip the alligator lead of your 12V test light to the battery negative (-) post.
- 3
Probe female terminal 1 of the coil pack connector with the tip of the test light.
Confirm that terminal 1 actually connects to the DK GRN/VIO wire of the connector.
NOTE: Be careful not to damage the female terminal with the probe —if you do, you'll have to replace the connector. - 4
Have your helper crank the engine.
- 5
The 12V test light should flash ON and OFF the whole time the engine cranks.
NOTE: Don't worry about what the test light does before cranking the engine —whether it comes on or not. What matters is that it flashes while the engine is cranking.
Let's find out what your test result means:
CASE 1: The 12V test light flashed ON and OFF the whole time the engine was cranking. This confirms the PCM is sending an ignition coil A activation signal to the coil pack.
You can conclude the ignition coil pack is bad and needs to be replaced if you've already confirmed:
- Spark plug wires for cylinders 1 and 4 aren't sparking (TEST 1).
- Ignition coil towers for cylinders 1 and 4 aren't sparking (TEST 3).
- The ignition coil A activation signal is present at terminal 1 (this section).
These are the coil packs I would go with —from Standard Motor Products and Motorcraft. Both are brands I've used my entire automotive repair career and ones I recommend:
- Standard Motor Products FD497T Ignition Coil (Amazon affiliate link).
- Motorcraft - IGN Coil DG536 (Amazon affiliate link).
CASE 2: The 12V test light DID NOT flash ON and OFF the whole time the engine was cranking. Double-check your test connections and repeat the test.
If the test light still doesn't flash, then ignition coil A isn't receiving its activation signal from the PCM.
The most likely cause of this missing coil A activation signal is an open-circuit problem in the DK GRN/VIO wire between the coil pack connector and the PCM. Your next step is to troubleshoot why the signal is missing and restore it to the circuit.
