TEST 5: Switching Signal For Cylinders 1 And 4

How To Test The 4 Cylinder Coil Pack (Ford 1.9L, 2.0L) How To Test The 4 Cylinder Coil Pack (Ford 1.9L, 2.0L)

In this test step, you're going to verify that the ignition coil (within the coil pack) that fires spark to cylinders 1 and 4 is being supplied with a Switching Signal.

This test is done with the coil pack connected to its connector.

Alright, let's start:

  1. With an appropriate tool, connect the black lead of the LED Light to the wire identified with the number 1 in the image viewer.
    1. This is the circuit that feeds the Switching Signal to the ignition coil (within the coil pack) that feeds spark to cylinders 1 and 4 simultaneously.
  2. Connect the red lead of the LED Light to the battery positive terminal.
  3. Have your helper crank the car (the car may start so be careful).
  4. If the car started, have your helper turn it off.
  5. If the Switching Signal is present, the LED Light will flash on an off the whole time the engine was cranking and during the time it was running.

Let's find out what your test result means:

CASE 1: If the LED light flashed on and off the whole time the engine was cranking or running. With this test result you can conclude that the PCM is providing the Switching Signal and the circuit is OK.

This test result confirms that the ignition coil pack is defective, replace it.

CASE 2: If the LED Light DID NOT flash on and off the whole time the engine was cranking or running. This test result usually means that there's either an open-circuit in the circuit between the connector and the PCM or the PCM is fried (altho' a fried PCM is rare). With this result you have eliminated the coil pack as the source of the Misfire Condition or No Spark Condition.

TEST 6: Switching Signal For Cylinders 2 And 3

How To Test The 4 Cylinder Coil Pack (Ford 1.9L, 2.0L) How To Test The 4 Cylinder Coil Pack (Ford 1.9L, 2.0L)

Here you're going to verify that the ignition coil (within the coil pack) that fires spark to cylinders 2 and 3 is receiving its switching signal from the PCM. This Signal test is done with the coil pack's connector connected to it.

These are the test steps:

  1. With an appropriate tool, connect the black lead of the LED Light to the wire identified with the number 3 in the image viewer.
    1. This is the circuit that feeds the Switching Signal to the ignition coil (within the coil pack) that feeds spark to cylinders 2 and 3 simultaneously.
  2. Connect the red lead of the LED Light to the battery positive terminal.
  3. Have your helper crank the car (the car may start so be careful).
  4. If the car started, have your helper turn it off.
  5. If the Switching Signal is present, the LED Light will flash on an off the whole time the engine was cranking and during the time it was running.

Let's find out what your test result means:

CASE 1: If the LED light flashed on and off the whole time the engine was cranking or running. This test result means that the PCM is providing the Switching Signal and the circuit is OK. This result confirms that the ignition coil pack is BAD, replace it.

CASE 2: If the LED Light DID NOT flash on and off the whole time the engine was cranking or running. This usually means that there's either an open-circuit problem in the wire between the connector and the PCM or the PCM is fried (altho' a fried PCM is rare). With this result you have eliminated the coil pack as the source of the Misfire Condition or No Spark Condition.