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Ignition coil

Symptom: Engine will not start.

Ignition coil

Fault symptom

Engine will not start.



Diagnostic procedure


1. Disconnect the ignition coil's HT cable from the distributor and connect a test spark plug to the cable with a gap of about 10 mm. Ground the spark plug and engage the starter motor. If the spark plug does not make a spark, continue with the next point.

2. With the ignition switch in the Drive position, check that the +15 pin of the ignition coil is supplied with battery voltage (from fuse 17).

Also check that pin 1 of the ignition coil is supplied with battery voltage.

If voltage is supplied to the +15 pin but not to pin 1, unplug the connector and check the resistance of the ignition coil across the +15 pin and pin 1 (primary winding).

The correct resistance is 0.52-0.76 ohms.

Also check the resistance of the secondary winding by taking a measurement across pin 1 and the HT terminal of the ignition coil.

The correct resistance is 7.2-8.2 ohms.

If the ignition coil is OK, proceed to point 3.

3. Plug in the connector and measure the voltage across pin 1 and the +15 pin.

With the ignition switch in the Drive position, a reading of 0 V should be obtained.

Also engage the starter motor, which should cause the voltmeter to pulse and give a reading of about 4-6 V.