FixVault

DTC P0604: Internal Control Module Random Access Memory (Ram) Error

WARNING: This page is about a different car, the 2011 Mercury Milan, 2011 Lincoln MKZ, 2011 Ford Fusion, 2010 Mercury Milan, and 2010 Ford Fusion. However, it is still accessible from the selected car via links, so may be relevant.
P0604 - INTERNAL CONTROL MODULE RANDOM ACCESS MEMORY (RAM) ERROR

Description:  Indicates the powertrain control module (PCM) RAM has been corrupted.
Possible Causes: 
  • Module reprogramming
  • Aftermarket performance products
  • PCM
Diagnostic Aids:  Reprogram or update the calibration. Check for other DTCs or drive symptoms for further action. Make sure to check for aftermarket performance products before installing a new PCM. If it is necessary to install a new PCM, refer to FLASH ELECTRICALLY ERASABLE PROGRAMMABLE READ ONLY MEMORY (EEPROM) , PROGRAMMING THE VID BLOCK FOR A REPLACEMENT PCM .
Application  Key On Engine Off  Key On Engine Running  Continuous Memory 
All Refer to the Description, Possible Causes and Diagnostic Aids for the DTC in table