Ignition Coil: Testing and Inspection

To perform a complete test of the ignition coil rail assembly including the three coils and their circuitry, refer to the DRB scan tool. Also refer to the appropriate Powertrain Diagnostics Procedures. To do an individual test of the coil assembly only, refer to the following:

Inspect the ignition coil for cracks and for any arcing. Arcing at the secondary end will carbonize the rubber spark plug boots, which if it is reconnected, may cause the coil to fail. Replace coil if any cracks or arcing is found.

Ignition Coil Connector Removal:

1. Disconnect coil primary electrical connector by pushing slide tab upward. After slide tab has been positioned upward, push in on secondary release lock on side of connector and pull connector from coil.

One of the 4 coil primary pins is used as a common battery feed (+) to all coils. The other 3 pins are used for (-) coil control for each individual coil. The coils are paired for cylinders 1-6, 2-5 and 3-4. Test the resistance (in ohms) of the primary side of the coil by attaching an ohmmeter across the battery feed (+) to any of the other (-) 3 pins. Refer to the IGNITION COIL RESISTANCE chart for resistance values. Replace coil if resistance values are incorrect.

The secondary circuit cannot be checked using an ohmmeter.

IGNITION COIL RESISTANCE
Primary Resistance 21-27° C (70-80° F) = 0.71-0.88 Ohms