Ignition Coil: Testing and Inspection

Coil Testing:

INSPECTION

1. Inspect the primary and secondary coil connections and wiring.

2. Inspect the ignition coil for signs of physical damage such as:

- Cracks in the case
- Signs of leakage
- Carbon tracks
- Burned, melted or discolored plastic

PRIMARY COIL RESISTANCE TEST

1. With ignition switch in the off position, disconnect the primary and secondary wires from the ignition coil.

2. Using an appropriate ohm meter with a minimum of 10 megohm impedance, measure the resistance between connector terminal 3 and each of the other terminals as follows:

Coil A (Cylinders 1 and 4) Terminals 3 and 2
Coil B (Cylinders 2 and 5) Terminals 3 and 1
Coil C (Cylinders 3 and 6) Terminals 3 and 4

- At 20°C (68°F) 0.67 - 0.81 ohms


SECONDARY COIL RESISTANCE TEST

1. With ignition switch in the off position, disconnect the primary and secondary wires from the ignition coil.

2. Using an appropriate ohm meter with a minimum of 10 megohm impedance, measure the resistance between each pair of high voltage terminals, as follows:

Coil A: Cylinders 1 and 4
Coil B: Cylinders 2 and 5
Coil C: Cylinders 3 and 6

- At 20°C (68°F) 11,300 - 15,300 ohms

NOTE: If any of the above test results are not within specifications or physical damage is apparent, replace the ignition coil.