I have a 1996 Ranger 2.3L 4 cylinder, I have put in a new key clyinder switch. Had no problem putting that in. The problem is that the Theft Detterent system will not clear. I have looked for a fuel system cut off switch underneith the dash of the truck and could not find. I have tried the 15 minute reset for the theft Deerent but that has not worked and the theft light will not clear at all. It should stop at 15 minutes and then reset for 15 more and then reset and 15 mores and should start after the 45 minute process. But no luck in this method. Will not even stop blinking after the first 15 minutes. Any Suggestions?

So I gather you replaced the ignition lock cylinder,and you now have non OEM ignition keys? It appears your truck possesses a PATS system that requires special keys with encoded chips the vehicle's PATS control module has to read and recognise before the vehicle can be started. So you need to have a couple PATS keys cut for the new lock , and have them programmed for use with your vehicle by a dealership. Or you can have a lock made to work with your original keys by a locksmith or dealership! GOOD LUCK!

OOPS! I forgot your vehicle is before the PATS time period! In your case we're dealing with a RAPS system. This system has a tamper detection sensor on the ignition lock cylinder. Make sure it's installed right!