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:
| • | An IC circuit |
| • | An ignition 1 voltage circuit |
| • | A ground circuit |
The sequencing and timing are ECM controlled. If the ECM detects an incorrect signal in the ignition control circuit, this DTC sets.
DTC Descriptors
This diagnostic procedure supports the following DTCs:
| • | DTC P0351 Ignition Coil 1 Control Circuit |
| • | DTC P0352 Ignition Coil 2 Control Circuit |
| • | DTC P0353 Ignition Coil 3 Control Circuit |
| • | DTC P0354 Ignition Coil 4 Control Circuit |
| • | DTC P0355 Ignition Coil 5 Control Circuit |
| • | DTC P0356 Ignition Coil 6 Control Circuit |
Conditions for Running the DTC
| • | The engine is running. |
| • | DTCs P0351, P0352, P0353, P0354, P0355, and P0356 run continuously once the above condition is met. |
Conditions for Setting the DTC
The ECM detects an incorrect signal in the IC circuit for more than one second.
Action Taken When the DTC Sets
| • | The control module stores the DTC information into memory when the diagnostic runs and fails. |
| • | The malfunction indicator lamp (MIL) will not illuminate. |
| • | The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Failure Records. |
| • | The driver information center, if equipped, may display a message. |
Conditions for Clearing the DTC
| • | 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 non-emission related diagnostic. |
| • | Clear the DTC with a scan tool. |
Test Description
The numbers below refer to the step numbers on the diagnostic table.
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This step determines if there is a condition in the ignition coil system.
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This step tests the ignition control circuit of the ignition coil. If the frequency is not within the specified range, there is a condition with the ignition control circuit or the ECM.
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This step tests the ignition 1 voltage supply to the ignition coil. The engine must be operating for this test. The fuel pump relay supplies the ignition 1 voltage to the ignition coils.
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This step tests the ground circuit of the ignition coil. A high resistance in the ground circuit will cause a condition. Repair the ground circuit if the resistance is more than the specified value.
Step | Action | Values | Yes | No | ||||
|---|---|---|---|---|---|---|---|---|
Schematic Reference: Engine Controls Schematics Connector End View Reference: Engine Controls Connector End Views or Engine Control Module Connector End Views | ||||||||
1 | Did you perform the Diagnostic System Check - Engine Controls? | -- | Go to Step 2 | |||||
Does DTC P0351-P0356 fail this ignition? | -- | Go to Step 4 | Go to Step 3 | |||||
3 |
Did the DTC fail this ignition? | -- | Go to Step 4 | Go to Intermittent Conditions | ||||
Is the frequency more than the specified value? | 10 Hz | Go to Step 6 | Go to Step 5 | |||||
5 | Test the appropriate ignition control circuit for the following conditions:
Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 14 | Go to Step 9 | ||||
Probe the ignition 1 voltage circuit of the ignition coil with a test lamp connected to a good ground. Refer to Circuit Testing in Wiring Systems. Does the test lamp illuminate? | -- | Go to Step 7 | Go to Step 10 | |||||
Measure the resistance of the ground circuit between the ignition coil and the ECM housing with a DMM. Refer to Circuit Testing in Wiring Systems. Is the resistance less than the specified value? | 5 ohms | 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 in Wiring Systems. 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 ECM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 14 | Go to Step 13 | ||||
10 | Repair the open or high resistance in the ignition 1 voltage circuit of the ignition coil. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | -- | Go to Step 14 | -- | ||||
11 | Repair the open or the high resistance in the ground circuit of the ignition coil. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | -- | Go to Step 14 | -- | ||||
12 | Replace the ignition coil. Refer to Ignition Coil Replacement . Did you complete the replacement? | -- | Go to Step 14 | -- | ||||
13 | Replace the ECM. Refer to Engine Control Module Replacement . Did you complete the replacement? | -- | Go to Step 14 | -- | ||||
14 |
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? | -- | System OK | |||||
