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EEPROM

The Electrically Erasable Programmable Read Only Memory (EEPROM) is a permanent memory that is physically soldered within the PCM. The EEPROM contains program and calibration information that the PCM needs to control powertrain operation. Unlike the PROM used in certain past applications, the EEPROM is not replaceable. If the PCM is replaced, the new PCM will need to be programmed. Techline equipment (Tech 2 Scan Tool) containing the correct program and calibration for the vehicle is required to program the PCM.