Freestar V6-4.2L VIN 2 (2004)
Engine Control Module: Service and Repair
Powertrain Control Module (PCM) Reset
POWERTRAIN CONTROL MODULE (PCM) RESET
Description
All OBD II scan tools support the powertrain control module (PCM) reset.
The PCM Reset allows the scan tool to command the PCM to clear all emission-related diagnostic information. When resetting the PCM, a DTC
P1000 will be stored in the PCM until all the OBD II system monitors or components have been tested to satisfy a drive cycle, without any other faults
occurring. For more information about a drive cycle, refer to Drive Cycles. See: Computers and Control Systems/Testing and Inspection/Monitors,
Trips, Drive Cycles and Readiness Codes/Drive Cycles
The following events occur when a PCM reset is performed:
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Clears the number of Diagnostic Trouble Codes (DTCs).
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Clears the DTCs.
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Clears the freeze frame data.
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Clears diagnostic monitoring test results.
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Resets status of the OBD II system monitors.
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Sets DTC P1000.
Resetting Keep Alive Memory (KAM)
Resetting Keep Alive Memory will return PCM memory to its default setting. Adaptive learning contents such as idle speed, refueling event, and fuel
trim are included. A PCM Reset (described above) is also part of a KAM Reset. Both can be useful in post repair retest.
After Keep Alive Memory has been reset, the vehicle may exhibit certain driveability concerns. It will be necessary to drive the vehicle to allow the
PCM to relearn values for optimum driveability and performance.
This function may not be supported by all scan tools. Refer to scan tool manufacturer's instruction manual.
If an error message is received or the scan tool does not support this function, disconnecting the battery ground cable for a minimum of 5 minutes may
be used as an alternative procedure.
