For 1990-2009 cars

### Diagnostic Instructions

• | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

• | Review Strategy Based Diagnosis for an overview of the diagnostic approach.

• | Diagnostic Procedure Instructions provides an overview of each diagnostic category.

### DTC Descriptors

DTC P2300: Ignition Coil 1 Control Circuit Low Voltage
DTC P2301: Ignition Coil 1 Control Circuit High Voltage
DTC P2303: Ignition Coil 2 Control Circuit Low Voltage
DTC P2304: Ignition Coil 2 Control Circuit High Voltage
DTC P2306: Ignition Coil 3 Control Circuit Low Voltage
DTC P2307: Ignition Coil 3 Control Circuit High Voltage
DTC P2309: Ignition Coil 4 Control Circuit Low Voltage
DTC P2310: Ignition Coil 4 Control Circuit High Voltage

### Diagnostic Fault Information

Circuit | Short to Ground | High Resistance | Open | Short to Voltage | Signal Performance
--- | --- | --- | --- | --- | ---
Ignition Coil 1 Control Circuit | P2300 | -- | -- | P2301 | --
Ignition Coil 2 Control Circuit | P2303 | -- | -- | P2304 | --
Ignition Coil 3 Control Circuit | P2306 | -- | -- | P2307 | --
Ignition Coil 4 Control Circuit | P2309 | -- | -- | P2310 | --

### Circuit/System Description

The ignition system uses individual ignition coil/module assemblies for each cylinder. The engine control module (ECM) controls the individual coils by transmitting timing pulses on the ignition control (IC) circuit of each ignition coil/module to enable a spark event. When the engine is running the ECM monitors each IC circuit for improper voltage levels. Each ignition coil/module has the following circuits:

• | An ignition voltage circuit

• | A ground

• | An IC control circuit

• | A low reference circuit

### Conditions for Running the DTCs

• | The engine speed is less than 6,000 RPM.

• | The ignition 1 voltage signal is between 9-18 volts.

• | DTCs P2300, P2301, P2303, P2304, P2306, P2307, P2309, P2310, run continuously when the above conditions are met.

### Conditions for Setting the DTCs

• | The ECM detects a short to ground on the circuit or the ignition coil/module for greater than 4 seconds continuously or 50 seconds cumulative.

| OR

• | The ECM detects a short to voltage on the circuit or the ignition coil/module for greater than 4 seconds continuously or 50 seconds cumulative.

### Action Taken When the DTC Sets

DTCs P2300, P2301, P2303, P2304, P2306, P2307, P2309, P2310, are Type B DTCs.

### Conditions for Clearing the MIL/DTC

DTCs P2300, P2301, P2303, P2304, P2306, P2307, P2309, P2310, are Type B DTCs.

### Reference Information

#### Schematic Reference

Engine Controls Schematics

#### Connector End View Reference

• | Engine Control Module Connector End Views

• | Engine Controls Connector End Views

#### Electrical Information Reference

• | Circuit Testing

• | Connector Repairs

• | Testing for Intermittent Conditions and Poor Connections

• | Wiring Repairs

#### DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

#### Scan Tool Reference

• | Scan Tool Data List

• | Scan Tool Data Definitions

• | Scan Tool Snapshot Procedure

### Circuit/System Verification

• | Start and idle the engine.

• | Observe the scan tool DTC Information and the Misfire Current Cylinder parameters. This will indicate the affected ignition coil/modules, and if the condition is current.

### Circuit/System Testing

1. Turn ON the ignition
2. Test the affected IC circuit for a short to ground or for a short to voltage.

⇒ | If a fault is found, repair the circuit as needed.

3. Start the engine.
4. Test the affected IC circuit for a short to ground or for a short to voltage.

⇒ | If a fault is found, repair the circuit as needed.

5. Ignition OFF, exchange the affected ignition coil/module with the ignition/coil module of a good cylinder.
6. Start the engine and observe the scan tool.

⇒ | If the DTC or the misfire transfers with the suspect ignition/coil module, replace as needed.

⇒ | If the DTC or the misfire does not transfer with the suspect ignition/coil module, replace the ECM.

### Repair Instructions

• | Ignition Coil Replacement

• | Control Module References for ECM replacement, setup, and programming

### Repair Verification

If the customer concern was a flashing MIL, then perform the following procedure:

1. Install any components that have been removed or replaced during diagnosis.
2. Perform any adjustments, programming or setup procedures that are required when a component is removed or replaced.
3. Clear the DTCs.
4. Turn OFF the ignition for 60 seconds.
5. If the repair was related to a DTC, duplicate the Conditions for Running the DTC and use the Freeze Frame/Failure Records, if applicable, in order to verify the DTC does not reset. If the DTC resets or another DTC is present, refer to the Diagnostic Trouble Code (DTC) List - Vehicle and perform the appropriate diagnostic procedure.
6. To verify that the performance of the catalytic converter has not been affected by the condition that set this DTC, perform the Repair Verification for DTC P0420. Refer to DTC P0420 .