Circuit Description
There are three dual-tower ignition coils that are part of the ignition control module (ICM). The ICM contains coil driver circuits that command the coils to operate. The ICM has the following circuits:
| • | An ignition voltage circuit |
| • | A ground |
| • | An IC 1 control circuit for the 1-4 ignition coil |
| • | An IC 2 control circuit for the 2-5 ignition coil |
| • | An IC 3 control circuit for the 3-6 ignition coil |
| • | A low reference circuit |
The powertrain control module (PCM) controls each dual-tower ignition coil by transmitting timing pulses on the IC control circuit to the ICM for the proper coil to enable a spark event.
If the PCM detects an open in one of the IC control circuits, it will set the following corresponding DTC:
| • | DTC P1351 for IC 1 control circuit |
| • | DTC P1352 for IC 2 control circuit |
| • | DTC P1353 for IC 3 control circuit |
If the PCM detects a short to voltage in one of the IC control circuits, it will set the following corresponding DTC:
| • | DTC P1351 and DTC P1361 for IC 1 control circuit |
| • | DTC P1352 and DTC P1362 for IC 2 control circuit |
| • | DTC P1353 and DTC P1363 for IC 3 control circuit |
Conditions for Running the DTC
The engine is running.
Conditions for Setting the DTC
The PCM detects an open or short to voltage in the IC control circuit for 30 out of 100 engine cycles.
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 3 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. |
Step | Action | Values | Yes | No |
|---|---|---|---|---|
Schematic Reference: Engine Controls Schematics Connector End View Reference: Powertrain Control Module Connector End Views or Engine Controls Connector End Views | ||||
1 | Did you perform the Diagnostic System Check -- Vehicle? | -- | Go to Step 2 | Go to Diagnostic System Check - Vehicle in Vehicle DTC Information |
2 |
Did the DTC fail this ignition? | -- | Go to Step 3 | Go to Intermittent Conditions |
3 |
Is the frequency within the specified range? | 3-20 Hz | Go to Step 5 | Go to Step 4 |
4 | Measure in DC Hertz between the IC control circuit of the ICM and a good ground with a DMM. Is the frequency within the specified range? | 3-20 Hz | Go to Step 7 | Go to Step 6 |
5 |
Does the cylinder misfire transfer with the suspected IC control circuit? | -- | Go to Step 8 | Go to Step 10 |
6 | Test the IC control circuit of the ICM for an open or a short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 14 | Go to Step 11 |
7 | Test the low reference circuit of the ICM for an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 14 | Go to Step 11 |
8 | Test the IC control circuit of the ICM for high resistance. 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 |
9 | Test the low reference circuit of the ICM for high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 14 | Go to Step 11 |
10 | Test for an intermittent and for a poor connection at the ICM. 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 |
11 | Test for an intermittent and for a poor connection at the powertrain control module (PCM). Refer 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 |
12 | Replace the ICM. Refer to Ignition Control Module Replacement . Did you complete the replacement? | -- | Go to Step 14 | -- |
13 | Replace the PCM. Refer to Powertrain Control Module Replacement . Did you complete the replacement? | -- | Go to Step 14 | -- |
14 |
Did the DTC fail this ignition? | -- | Go to Step 3 | 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 in Vehicle DTC Information | System OK |
