Circuit Description
The Powertrain Control Module (PCM) is the control center of the fuel injection system. The PCM receives the information from the various sensors, and controls the systems that affect the vehicle performance. The PCM also performs the diagnostic function of the system. The PCM can recognize the operational problems, alert the driver through the malfunction indicator lamp (MIL), also known as the Check Engine lamp , and store DTCs which identify the problem areas in order to aid you in making repairs. An electrically erasable programmable read only memory (EEPROM) houses the program information and the calibrations required for the engine, the transmission, and the powertrain diagnostics operation. The programming of the EEPROM can be updated by reprogramming the PCM.
Conditions for Setting the DTC
The PCM is improperly programmed.
Action Taken When the DTC Sets
| • | The PCM will record operating conditions at the time during which the diagnostic fails. This information will store in the Failure Records buffer. |
| • | A history DTC stores. |
Conditions for Clearing the MIL/DTC
| • | A history DTC will clear after 40 consecutive warm up cycles without a fault. |
| • | Use a scan tool to clear the DTCs. |
Test Description
The numbers below refer to the step numbers on the diagnostic table.
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Refer to the latest Techline™ information for programming procedures.
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The replacement PCM must be programmed and the Crankshaft Position System Variation Learn procedure must be performed.
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
1 | Did you perform the Powertrain On-Board Diagnostic (OBD) System Check? | -- | ||
2 | Was the PCM just replaced? | -- | ||
Does the DTC reset? | -- | |||
Important:: The replacement PCM must be programmed. Refer to Powertrain Control Module Replacement/Programming . Did you complete the replacement? | -- | -- | ||
5 |
Does the DTC reset? | -- | System OK |
