Hi, I've recently bought a '98 Trooper with only 1 keyless entry fob, so I bought another on eBay today but can't find the programming instructions anywhere (short of paying $10 for them on eBay). If anyone knows what to do please let me know. Thanks in advance!

http://www.geocities.com/endre_rl/isuzufaq.htm#faq41 Has the info you need and a whole lot more.