P0351

Diagnostic Chart:

Schematic:

The PCM controls spark timing and dwell (spark On-time) under all engine running conditions. The Electronic Ignition (EI) module has the ability to charge and discharge the coil packs based on PCM control. The PCM uses a high control signal of near 5 volts to charge up the coil and a low control signal of near 0 volts to discharge the coil. If the coil is charged and the control signal is low, the coil will fire through its secondary towers. DTC P0351 sets when a short to ground exists on IC circuit 1 and 4 during engine crank or when engine is running.

DTC PARAMETERS
DTC P0351 will set if a short to ground occurs on IC circuit 1 and 4 during engine crank or run.

DTC P0351 diagnostic runs continuously when the engine is cranking or running.

DTC P0351 is a type D DTC.

DIAGNOSTIC AIDS
The IC circuit 1 and 4 consists of the EI module, circuit 423 and the PCM.

Voltage on circuit 423 with EI module disconnected and ignition On, engine Off should read between 3.5 and 5 volts.

A short to ground on IC circuit 1 and 4 will cause a misfire on both cylinders 1 and 4. Use Scan tool to monitor MISFIRE CURRENT CYLs #1 and #4 to locate an intermittent problem.

The IC CYL. #1 and 4-LOW VOLT test parameter on Scan Tool can also be used to locate an intermittent problem. If a fault (short to ground) occurs when engine is running, the Scan tool will display TEST FAIL.

A secondary ignition problem on cylinder #1 or #4 will NOT cause DTC P0351 to set.