The ignition control (IC) module controls spark timing when the engine is cranking. During this Bypass mode of operation, the IC module triggers each ignition coil in the proper sequence at a pre-calibrated timing advance. The IC module is connected directly to the powertrain control module (PCM) and includes the following circuits:

During engine cranking and certain low RPM engine running conditions, the IC module controls the ignition timing at a fixed 10 degree advance. This is called bypass mode. When the PCM receives the 3X low resolution engine speed signal from the IC module, 5 volts is applied to the IC timing signal circuit from the PCM. This signals the IC module to allow the IC timing by the PCM. The PCM sends spark timing signals to the IC module on the IC timing control circuit. The PCM monitors the IC timing control circuit for errors.

Important: The PCM detects engine movement by sensing the airflow through the mass air flow (MAF) sensor is more than 3 g/s.

The PCM detects a fault in the IC timing control circuit for more than 9 seconds.

DTC P0350 is a Type B DTC.

DTC P0350 is a Type B DTC.

Schematic Reference

Engine Controls Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Electronic Ignition (EI) System Description

Electrical Information Reference

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

1. Start the engine. The engine should start and run.
2. Monitor the Ignition Mode parameter. The parameter should transition from Bypass to IC when the engine is cranking or running.
3. Operate the vehicle within the Conditions for Running the DTC to verify the DTC does not reset. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

1. Ignition OFF, disconnect the IC module connector. Test for less than 5 ohms between the IC module low reference circuit IC module terminal L and ground.

⇒	If greater than the specified value, test the ground circuit for an open/high resistance.

2. Test for less than 3 ohms between the IC module ground circuit IC module terminal K and battery ground.

⇒	If greater than the specified value, test the ground circuit for an open/high resistance.

3. Ignition ON, test for B+ between the IC module ignition voltage circuit IC module terminal P and ground.

⇒	If less than the specified range, test the IC module ignition voltage circuit IC module terminal P for an open/high resistance or short to ground.

4. Ignition ON, using a jumper wire connected to B+, momentarily touch the low resolution engine speed signal circuit IC module terminal D at the IC module harness connector repeatedly, while measuring the frequency with a DMM. The frequency should be greater than 0 Hz.

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If the frequency is 0 Hz, test the IC timing control circuit IC module terminal A for an open/high resistance, short to ground, or short to voltage. If the circuit tests OK, test the IC timing signal circuit IC module terminal B for a short to ground. If both circuits test OK, replace the IC module.

⇒	If the frequency is greater than 0 Hz, replace the PCM.

5. If all circuits test OK, replace the IC module.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for IC module and PCM replacement, setup, and programming