Hello Mike, If your looking at the engineer book it will tell you how to reset it back to 9999 (reset nvm), if your looking at the user guide it won't and you will need the engineer book to re programme it anyway.
if your in my area Bury Lancs I can sort it for you, if not i can post a message and hopefully an engineer in your area will pick it up.
Regards
rob
rpea52@aol.com
Rob
January 2008