Ignition Coil Pack: Testing and Inspection

CHECKING IGNITION COILS

NOTE:
Check connecting wires between power output stage and ignition coils as well as between ignition coils and terminals in connector blocks for corrosion or damaged insulation.

CHECKING SECONDARY RESISTANCE
- Disconnect ignition wires from ignition coils.

Ignition Coil Resistance:

- Connect multimeter (Fluke 83 or equivalent) between both ignition wiring connections of ignition coil being tested.
^ Specified reading: 9-14K ohms each

If specified value is not obtained on any one ignition coil:
- Replace ignition coil.

CHECKING PRIMARY RESISTANCE
- Disconnect 3-pin connectors from ignition coil and power output stage.
- Check connectors for loose, corroded or displaced terminals and repair as necessary.

NOTE:
The correct terminal assignment in the connector is essential since positive voltage is supplied via all three terminals to the ignition coils.

3-Pin Connector:

Ignition Coil Connector

3-Pin Connector:

Power Stage Connector

- Connect multimeter between terminal 1 of ignition coil harness connector and terminal 1 of power output stage harness connector.
^ Specified value: 0.5-1.0 ohm for each coil
- Repeat test for corresponding connector terminals 2 and 3.
^ Specified value must be obtained for all three measurements

If specified values are not obtained:
- Replace ignition coil.

CHECKING BATTERY POSITIVE VOLTAGE (B+) SUPPLY FOR IGNITION COILS

^ Circuit breaker -S64- must be OK (yellow holder in electronics box, passenger side footwell)

- Disconnect white harness connector at connector holder (on engine bulkhead) Item 1B.
- Switch ignition on.
- Connect US 1115 LED tester or equivalent between Ground (GND) and all three terminals of connector in sequence.
^ LED must light up each time

If LED does NOT light up:
- Check for open circuit using wiring diagram and repair as necessary.