Ignition Coil: Testing and Inspection

IGNITION COIL

SPARK TEST

1. Disconnect the ignition coil lead from the distributor.
2. Hold it with insulated pliers approx. 5-1Omm (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, check for voltage at the positive (+) terminal of the ignition coil with the ignition switch at ON position.


Voltage: Battery positive voltage


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





Primary Coil Winding







Using an ohmmeter, measure the resistance of the primary coil winding. If it is not within specification, replace the coil.


Primary coil winding resistance (at 20°C / 68°F)

JE 3.0 : 0.72-O.88 Ohms







Secondary Coil Winding






Using an ohmmeter, measure the resistance of the secondary coil winding. It it is not within specification, replace the coil.


Secondary coil winding resistance (at 20°C / 68°F)

JE 3.0 : 10-30 K Ohms




Insulation of Case







Using a 500V megger tester, measure the insulation resistance between the primary terminal and the case.


Resistance: 10 M Ohms min.