EEPROM (Electrically Erasable Programmable Read Only Memory)

An EEPROM  is a soldered in chip which is not removable from the control module. As their name Soldered in EEPROM implies, EEPROMS can be electrically erased and reprogrammed without opening the control module. This is known as "Flash Programming". 

In either case, the E or EE PROM stores the loaded program data including:

• Characteristic maps for;

  Ignition, Injection, Purge control, etc...

• Characteristic curves.
• Control constants.
  Fig 1: Identifying EEPROM Chip

  Courtesy of BMW OF NORTH AMERICA, INC.