Engine Control Module (ECM) Description: EEPROM
WARNING: This page is about a different car, the 2004 Cadillac CTS. However, it is still accessible from the selected car via links, so may be relevant.
The electronically erasable programmable read only memory (EEPROM) is a permanent memory that is physically part of the ECM. The EEPROM contains program and calibration information that the ECM needs in order to control the powertrain operation.
Special equipment, as well as the correct program and calibration for the vehicle, are required in order to reprogram the ECM.