For 1990-2009 cars

### Circuit Description

The ignition system on this engine uses individual ignition coils and ignition control (IC) circuits for each cylinder. The engine control module (ECM) controls the ignition system operation. The ECM controls each coil using the IC circuits. The ECM commands the IC circuit low when a spark event is requested. Each ignition coil is supplied the following circuits:

• | The ignition control circuit

• | The ignition 1 voltage circuit

• | Two ground circuits

The sequencing and timing are ECM controlled. If the ECM detects the ignition control circuit is shorted to ground, this DTC sets.

### DTC Descriptors

This diagnostic procedure supports the following DTCs:

• | DTC P2300 Ignition Coil 1 Control Circuit Low Voltage

• | DTC P2303 Ignition Coil 2 Control Circuit Low Voltage

• | DTC P2306 Ignition Coil 3 Control Circuit Low Voltage

• | DTC P2309 Ignition Coil 4 Control Circuit Low Voltage

• | DTC P2312 Ignition Coil 5 Control Circuit Low Voltage

• | DTC P2315 Ignition Coil 6 Control Circuit Low Voltage

### Conditions for Running the DTC

• | The engine is running.

• | The engine speed is between 600-5,000 RPM.

• | The ignition voltage is between 10-18 volts.

• | This DTC runs continuously once the above conditions are met and the crankshaft rotates for 20 times.

### Conditions for Setting the DTC

• | The ECM detects the ignition control circuit is shorted to ground.

• | The above condition is present for less than 4 seconds.

### Action Taken When the DTC Sets

• | The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.

• | The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records.

### Conditions for Clearing the MIL/DTC

• | The control module turns OFF the malfunction indicator lamp (MIL) after 4 consecutive ignition cycles that the diagnostic runs and does not fail.

• | A current DTC, last test failed, clears when the diagnostic runs and passes.

• | A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.

• | Clear the MIL and the DTC with a scan tool.

### Diagnostic Aids

• | Use the J 35616-A/BT-8637 Connector Test Adapter Kit for any test that requires probing the ECM harness connector or a component harness connector.

• | The lower connector of the ECM is connector C1 and the upper connector of the ECM is connector C2. Refer to Engine Controls Component Views .

• | Inspect the ignition coils for aftermarket devices. An aftermarket device connected to the ignition coil circuits, may cause this DTC to set.

• | For an intermittent condition, refer to Intermittent Conditions .

### Test Description

The number below refers to the step number on the diagnostic table.

1. This step tests that the ECM is commanding the ignition coil ON and OFF via the ignition control circuit. If the frequency is not between 3-20 Hz, test the ignition control circuit for a short to ground.

#### P2300, P2303, P2306, P2309, P2312, or P2315

Step | Action | Values | Yes | No
--- | --- | --- | --- | ---
Schematic Reference: Engine Controls Schematics
1 | Did you perform the Diagnostic System Check - Vehicle? | -- | Go to Step 2 | Go to Diagnostic System Check - Vehicle
2 |

1. Start the engine.
2. Observe the DTC Info with a scan tool.

Does DTC P2300, P2303, P2306, P2309, P2312, or P2315 fail this ignition?

--

Go to Step 4

Go to Step 3

3 |

1. Observe the Freeze Frame/Failure Records for this DTC.
2. Turn OFF the ignition for 30 seconds.
3. Start the engine.
4. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records.

Did the DTC fail this ignition?

--

Go to Step 4

Go to Diagnostic Aids

4 |

1. Turn OFF the engine.
2. Disconnect the appropriate ignition coil electrical connector.
3. Start the engine.
4. Measure the frequency at the ignition control (IC) circuit using the DMM set to the DC Hertz scale. Refer to Measuring Frequency .

Is the frequency within the specified range?

3-20 Hz

Go to Step 6

Go to Step 5

5 | Test the appropriate IC circuit for a short to ground. Refer to Testing for Short to Ground . Did you find and correct the condition? | -- | Go to Step 14 | Go to Step 9
6 |

1. Turn the ignition switch to ON position, with the engine OFF.
2. Probe the ignition 1 voltage circuit of the ignition coil with a test lamp connected to battery ground. Refer to Troubleshooting with a Test Lamp .

Does the test lamp illuminate?

--

Go to Step 7

Go to Step 10

7 | Probe both of the ground circuits of the ignition coil with a test lamp connected to B+. Refer to Troubleshooting with a Test Lamp . Does the test lamp illuminate at both circuits? | -- | Go to Step 8 | Go to Step 11
8 | Test for an intermittent and for a poor connection at the ignition coil. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs . Did you find and correct the condition? | -- | Go to Step 14 | Go to Step 12
9 | Test for an intermittent and for a poor connection at the engine control module (ECM). Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs . Did you find and correct the condition? | -- | Go to Step 14 | Go to Step 13
10 |

1. Repair the open or grounded ignition 1 voltage circuit of the ignition coil. Refer to Wiring Repairs .
2. Replace the fuse if necessary.

Did you complete the repair?

--

Go to Step 14

--

11 | Repair the open in the ground circuits for the ignition coil. Refer to Wiring Repairs . Did you complete the repair? | -- | Go to Step 14 | --
12 | Replace the ignition coil. Refer to the appropriate procedure:

• | Ignition Coil Replacement - Bank 1

• | Ignition Coil Replacement - Bank 2

Did you complete the replacement?

--

Go to Step 14

--

13 | Replace the ECM. Refer to Control Module References for replacement, setup, and programming. Did you complete the replacement? | -- | Go to Step 14 | --
14 |

1. Clear the DTCs with a scan tool.
2. Turn OFF the ignition for 30 seconds.
3. Start the engine.
4. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records.

Did the DTC fail this ignition?

--

Go to Step 2

Go to Step 15

15 | Observe the Capture Info with a scan tool. Are there any DTCs that have not been diagnosed? | -- | Go to Diagnostic Trouble Code (DTC) List - Vehicle | System OK