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Home >> Ford >> 2005 >> Excursion 6.0 P, 4WD >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> Engine Controls - Pinpoint Tests - 6.0L Diesel (99P F450/550) >> Pinpoint Test AA: Powertrain Control Module (PCM) Read Only Memory (ROM) Failure >> Test Procedure
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Test Procedure

  1. AA1 DIAGNOSTIC TROUBLE CODE (DTC) P0605 
    • DTC P0605 is set when a ROM failure is detected in the PCM.
    • Possible causes:
      • internal PCM failure
      • incorrect PCM calibration
    • Key ON, engine OFF.
    • Carry out the Key On Engine Off (KOEO) on-demand self-test.

    Is DTC P0605 present? 

    Yes No
    REFLASH the PCM. CLEAR the DTCs. REPEAT the self-test. If DTC P0605 is present again, INSTALL a new PCM. UNABLE to duplicate the condition. CHECK for a loose connection, and damaged or corroded terminals. WIGGLE the harness attempting to recreate the fault. REPAIR as necessary. REFER to SYMPTOM CHARTS - 6.0L DIESEL if a driveability concern exists.