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 Descriptor

DTC P2300 00: Ignition Coil 1 Control Circuit Low Voltage
DTC P2301 00: Ignition Coil 1 Control Circuit High Voltage
DTC P2303 00: Ignition Coil 2 Control Circuit Low Voltage
DTC P2304 00: Ignition Coil 2 Control Circuit High Voltage
DTC P2306 00: Ignition Coil 3 Control Circuit Low Voltage
DTC P2307 00: Ignition Coil 3 Control Circuit High Voltage
DTC P2309 00: Ignition Coil 4 Control Circuit Low Voltage
DTC P2310 00: Ignition Coil 4 Control Circuit High Voltage

### Diagnostic Fault Information

Circuit | Short to Ground | High Resistance | Open | Short to Voltage
--- | --- | --- | --- | ---
Ignition Coil 1 Control Circuit | P2300 00 | -- | -- | P2301 00
Ignition Coil 2 Control Circuit | P2303 00 | -- | -- | P2304 00
Ignition Coil 3 Control Circuit | P2306 00 | -- | -- | P2307 00
Ignition Coil 4 Control Circuit | P2309 00 | -- | -- | P2310 00

### Circuit/System Description

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

• | Ignition voltage

• | Ground

• | ignition control for each coil

• | Low reference

### Conditions for Running the DTC

• | The engine speed is less than 6000 RPM.

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

• | DTCs P2300 00, P2301 00, P2303, P2304 00, P2306 00, P2307 00, P2309 00, P2310 00 run continuously when the above conditions are met.

### Conditions for Setting the DTC

The ECM detects a short to ground on the circuit or the ignition coil for greater than 4 s continuously or 50 s cumulative.

or

The ECM detects a short to voltage on the circuit or the ignition coil for greater than 4 s continuously or 50 s cumulative.

### Action Taken When the DTC Sets

DTCs P2120 00, P2122 00, P2123 00, P2125 00, P2127 00, P2128 00, and P2138 00 are Type A DTCs.

### Conditions for Clearing the DTC

DTCs P2120 00, P2122 00, P2123 00, P2125 00, P2127 00, P2128 00, and P2138 00 are Type A DTCs.

### Reference Information

#### Schematic Reference

Engine Controls Schematics

#### Connector End View Reference

Component 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

Control Module References for scan tool information

### Circuit/System Verification

1. Start and idle the engine.
2. Observe the scan tool misfire current cylinder parameters. The counters should not be incrementing.
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.

### Circuit/System Testing

1. Turn ON the ignition, with the engine OFF.
2. Disconnect the T8 Ignition Coil Connector and test affected T8 Ignition Coil IC circuit terminal for a short to ground or for a short to voltage for the appropriate T8 ignition coil:

• | T8 Ignition Coil 1 Control Circuit terminal D

• | T8 Ignition Coil 2 Control Circuit terminal E

• | T8 Ignition Coil 3 Control Circuit terminal F

• | T8 Ignition Coil 4 Control Circuit terminal G

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

3. Ignition OFF, exchange the affected T8 Ignition Coil module with an T8 Ignition Coil module of a good cylinder.
4. Start the engine and observe the scan tool.

⇒ | If the DTC or the misfire transfers with the suspect ignition coil/module, replace T8 Ignition Coil as needed.

⇒ | If the DTC or the misfire does not transfer with the suspect T8 Ignition Coil module, replace the K20 Engine Control Module (ECM).

### Repair Instructions

• | Ignition Coil Replacement

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

### Repair Verifications

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 s.
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 00. Refer to DTC P0420.