• | 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. |
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
---|---|---|---|---|
Ignition 1 Voltage | **P0351, P0352, P0353, P0354 | *P0351, P0352, P0353, P0354 | -- | -- |
Ignition Coil 1 Control Circuit | P0351 | P0351 | P0351 | -- |
Ignition Coil 2 Control Circuit | P0352 | P0352 | P0352 | -- |
Ignition Coil 3 Control Circuit | P0353 | P0353 | P0353 | -- |
Ignition Coil 4 Control Circuit | P0354 | P0354 | P0354 | -- |
Ignition Fail-Safe Circuit | **P0351, P0352, P0353, P0354 | *P0351, P0352, P0353, P0354 | **P0351, P0352, P0353, P0354 | -- |
Ignition Coil Ground Circuit | -- | *P0351, P0352, P0353, P0354 | -- | -- |
* This circuit has individual branches to each coil as well as the shared connection to the voltage supply, PCM, or ground. If the open/high resistance is in the individual branch circuit or coil, only a single coil specific DTC will set. **This fault causes all ignition coil DTCs to set simultaneously |
This diagnostic monitors the primary circuitry of individual ignition coils for the successful completion of an ignition event. The ignition trigger signal and ignition fail-safe input signal provide crucial information in the control of ignition system timing and the activation of the fail-safe function. Based on the initial timing angle, calculated from the crankshaft and the camshaft position signals, the powertrain control module (PCM) calculates the ignition trigger signal. The ignition trigger signal is then sent to the ignition control circuitry located in each ignition coil. The ignition control circuitry initiates the ignition dwell period by commanding the power transistor ON. When the PCM determines the proper time to provide spark, the PCM turns OFF the ignition trigger signal. In response to the PCM signal, the ignition coil control circuitry turns OFF the power transistor, producing a high voltage discharge from the secondary coil windings. After the spark has occurred, the control circuitry sends an ignition fail-safe input signal back to the PCM, confirming that an ignition event has taken place. If the ignition fail-safe input signal is not received by the PCM, a cylinder specific DTC will set. The ignition coils consist of the following circuits:
• | The ignition 1 voltage circuit |
• | The ignition trigger control circuit |
• | The ignition fail-safe circuit |
• | The ground circuit |
• | The engine is cranking or running. |
• | The DTCs run continuously once the above condition is met. |
No ignition coil fail-safe input signal is received by the PCM for 2 consecutive ignition trigger signal cycles.
• | DTCs P0351, P0352, P0353, and P0354 are Type A DTCs. |
• | The PCM enters the fail-safe function and begins Fuel Cut-off mode operation during high engine load operation. |
DTCs P0351, P0352, P0353, and P0354 are Type A DTCs.
Inspect for the following conditions:
• | An interruption of the ground circuit or voltage supply to the ignition coil will prevent a proper ignition event from taking place. DTC P0351 through P0354 can set if there is a intermittent fault in any of the ignition coil circuits. |
• | If DTCs P0351, P0352, P0353, and P0354 are present, the fault is located in the shared electrical circuits or shared components of the ignition coils. |
• | The scan tool data parameters for Misfire Current Cylinder # are frozen at the time the MIL illuminates when the DTC sets. |
• | Inspect the noise filter for an internal short or low resistance. The ignition coil may not receive adequate voltage during high load conditions if the noise filter is faulty. A good noise filter will indicate infinite resistance (OL) with a DMM after the capacitor inside the filter is charged up. |
Electronic Ignition (EI) System Description
Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Control Module References for scan tool information
⇒ | If greater than the specified range, test the coil ground circuit for an open/high resistance. |
⇒ | If the test lamp does not illuminate, test the ignition 1 voltage circuit for a short to ground or an open/high resistance. If the circuit tests normal, test the IG2 ignition relay. Refer to Ignition Relay Diagnosis. |
Important: Ensure that DTCs are cleared before performing this test.
⇒ | If less than the specified range, test the control circuit for short to ground or an open/high resistance. If the circuit tests normal, replace the PCM. |
⇒ | If greater than the specified range, test the control circuit for a short to voltage. If the circuit tests normal, replace the PCM. |
⇒ | If less than the specified range, test the fail-safe circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the PCM. |
⇒ | If greater than the specified range, test the fail-safe circuit for a short to voltage. If the circuit tests normal, replace the PCM. |
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
• | Control Module References for control module replacement, setup, and programming |