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Service Programming System (SPS) - Types of Programmable Memory

EEPROM: Electrically erasable programmable read only memory - This type of memory allows selected portions of memory to be programmed while other portions remain unchanged.

Certain learned values reside in EEPROM. The following information resides in EEPROM:
^ The Vehicle Identification Number (VIN)
^ The crankshaft variation learned position
^ The software/calibrations identification numbers
^ The control module security information

Flash Memory: Flash read only memory - Flash memory has increased memory storage capacity. During programming, all information within memory is erased, and then replaced with entirely new information.

Most control modules have both types of memory. The software/calibrations reside in the flash memory.