DTC P0602: Control Module Not PROGRAMED: Description
WARNING: This page is about a different car, the 2001 Cadillac Seville, 2001 Cadillac Eldorado, and 2001 Cadillac DeVille. However, it is still accessible from the selected car via links, so may be relevant.
Powertrain Control Module (PCM) uses an Electrically Erasable Programmable Read Only Memory (EEPROM) to store software and calibration information. EEPROM is not replaceable, PCM must be replaced. Replacement PCM does not contain final program information. Replacement PCM must be programed. If replacement PCM is not programmed, DTC P0602 will set. When DTC sets, PCM disables fuel pump relay and fuel injectors.