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 12 volts with engine running, and with engine RPM less than 3000, and none of the coils in dwell when checked.

SET CONDITION:
Peak current is not achieved with 5.75 milliseconds 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 Automatic Shutdown (ASD) relay. The Powertrain Control Module (PCM) controls the individual primary circuits: cavity 21 controls coils # 1 and # 4, and cavity 1 controls coils # 2 and # 3. 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