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) (Check Engine), and store a 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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The Powertrain OBD System Check prompts you to complete some of the basic checks and to store the freeze frame and failure records data on the scan tool if applicable. This creates an electronic copy of the data captured when this DTC set. The scan tool stores this data for later reference.
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Refer to the latest Techline information for programming procedures.
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Reprogram the replacement PCM and the perform the crankshaft position system variation learn procedure. Refer to the latest Techline procedures for PCM reprogramming.
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
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 repair? | -- | -- | ||
5 |
Does the scan tool indicate that this diagnostic has ran and passed? | -- | ||
6 | Check to see if any additional DTCs are set. Does the scan tool display any DTCs that you have not diagnosed? | -- | Go to the applicable DTC table | System OK |
