DTC P0605: Internal Control Module Read Only Memory (ROM) Error

WARNING: This page does not describe the selected car, but rather 33 other vehicles, including the 2010 Mercury Mountaineer, 2010 Mercury Milan, 2010 Mercury Mariner, 2010 Mercury Grand Marquis, and 2010 Lincoln Town Car. However, it is still accessible from the selected car via links, so may be relevant.

DTC P0605: INTERNAL CONTROL MODULE READ ONLY MEMORY (ROM) ERROR

Description:	The powertrain control module (PCM) ROM has been corrupted.
Possible Causes:	An attempt was made to change the calibration Module programming error Aftermarket performance products PCM
Diagnostic Aids:	Reprogram the vehicle identification (VID) block (use as built data). Check for other DTCs or drive symptoms for further action. Make sure to check for aftermarket performance products before installing a new powertrain control module (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 appropriate DTC.