Ignition Coil: Testing and Inspection

IGNITION COIL
Inspection / Spark Test
1. Disconnect the high-tension lead from the distributer




2. Hold the lead with insulated pliers 5-10 mm (0.20-0.39 in) from a ground.
3. Crank the engine and verify that a strong blue spark is visible.




4. If there is no spark, disconnect the connector from the Ignition Coil and check for voltage at the positive (+) terminal of the connector as shown with the ignition switch turned to ON.

Voltage: Battery positive voltage

5. If there is no voltage, check the main fuse, ignition switch, and wiring harness.




Primary Coil Winding
1. Measure the resistance of the Primary Coil Winding.

Resistance at 20°C (68°F)
1. 0.7-1.0 Ohms
2. 0.9-1.1 k Ohms

2. If not within specification, replace the Ignition Coil.




Secondary Coil Winding
1. Measure the resistance of the secondary coil winding.

Resistance at 20°C (68°F) 9-17 k Ohms

2. If not within specification, replace the Ignition Coil.





Insulation of Case
1. Using a 500V megger tester, measure the insulation resistance between each terminal and the case.

Specification: 10 Meg Ohms min.

2. If not within specification, replace the Ignition Coil.