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Home >> Ford >> 2004 >> Excursion 6.0 P, RWD >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> Engine Controls - Pinpoint Tests - 6.0L Diesel (99P E-Series & 99P F450/550) >> Pinpoint Test Z: Continuous Memory Failure >> Introduction >> Circuit Function
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Circuit Function

The powertrain control module (PCM) stores the vehicle operating conditions in random access memory (RAM) and utilizes this information to compensate for component variability. The keep-alive power (KAPWR) circuit supplies battery voltage (B+) to the PCM to maintain the memory contents when the ignition switch is off.

CAUTION: The PCM harness connectors must be properly seated and the connector latch properly attached to eliminate possible driveability concerns or a no-start condition. Installing PCM connectors on an angle may cause an improper connection, misdiagnosis, and damaged components. Install the connector until the lever pivots and seats itself. Apply light pressure to get the connector into position on the PCM and then fully seat the connector.
NOTE: Visually inspect the harness connectors for corrosion, damage, proper mating and correct pin tension.
NOTE: When the PCM is disconnected additional DTCs will be set. Clear all DTCs after restoring the vehicle.
Fig 1: Identifying PCM Body Harness Connector Terminals
G03532283Courtesy of FORD MOTOR CO.