For 5/03 and 5/04 Processors:
1) Power down processor.
2) Pull processor out of rack and disconnect battery cable.
3) Find the VBB and GND solder pads on the back side of the processor (5/03 - on the back side of mother board where the battery would be located. 5/04 - on the back side of mother board approx. 1 inch from the back connector edge of the mother board and about centered from the top/bottom of mother board.)
4) Using something metal (a paper clip will do), short the VBB and GND terminals for 60 seconds.
5) Reconnect battery and insert processor into rack.
6) Power up processor.
(See AB Publication 1747-6.2 SLC 500 Modular Hardware Style Installation and Operation Manual, Troubleshooting Chapter, "Returning Processor to Initial Factory Conditions" for pictures of mother board and locations of VBB and GND solder pads.)