Ignition Coil: Testing and Inspection

SPARK TEST

Ignition Coil Testing:

CAUTION: To reduce the hazard of fire or explosion, ensure that no fuel leaks exist before conducting this test. Do not check for spark near the battery.

1. Disconnect ignition coil lead from distributor.
2. With insulated pliers, hold end approximately 0.20 - 0.39 in (5 - 10 mm) from ground and crank engine.
3. Verify that a strong blue spark jumps the gap.
4. If there is no spark, check for battery voltage at the coil positive terminal with ignition switch "ON."
5. If there is no voltage, check main fuse, ignition switch. Repair the problem as required.

RESISTANCE CHECK

Ignition Coil Resistance Check:

1. Check primary resistance across coil terminals as indicated on image.

0.81 - 0.99 ohms

2. Check secondary resistance as indicated on image.

10 - 16K ohms

3. Check insulation resistance between primary positive terminal and coil case.

10M ohms min.

4. Replace coil if it does not test as specified.