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Ignition Coil Primary Circuit

Name of Code:
Ignition Coil Primary Circuit

When Monitored:
With battery voltage greater than 8 volts during engine cranking or greater than 2 volts with engine running, and none of the coils in dwell when checked.

Set Condition:
Peak current is not achieved with 2.5ms of dwell. It takes 3 seconds during cranking or up to 6 seconds while running to set

Theory of Operation:
The ignition coil is supplied 12 volts from the ASD relay. The PCM controls the individual primary circuits. The amount of dwell time is based on crankshaft speed and camshaft position.

Possible Causes:
- Open or shorted ignition coil driver circuit
- Open ignition coil primary
- Open ASD output circuit
- Failed PCM
- Connector terminals
- Connector wires