Check to see if your CDL work too. It could be one of two problems. One problem is the park/neutral switch has gone bad. It's a switch on the bottom side of the transmittion and suppose to tell the truck if your in gear or park/neutral. This lets you take the key out of the ignition, start the truck, operate the cdl. Other issue, which is what happened to me, the mfu (multi function unit) has gone bad. It controls the cdl, key, and transmittion interlocks. Afraid to say the only way I got it to stop and allow my cdl to work again was to replace both. However I probably could have done just the mfu and been okay. I just tried the switch first and it cost only $33 from roversnorth. To kill the sounder pull fuse #13. Issue is your key interlock, cdl interlock, rear wiper, intermittant wiper and window washer won't work. You'll be able to squirt the blue juice but have to manually switch on the lighters. Your CDL will engage, but you can move it out of gear, in and out of lock while in gear or motion.
Bad idea to do that. Also you will be able to take the key out of the ignition while in gear and start while in gear. So your truck will roll away if the parking brakes not on or your in park. Starting in gear, well don't do it in a crowded parking lot. I was told (don't know if its true) the 94-97 mfu's are prone to fail around 100k miles. Good luck! This problem frustrated me this past summer, couldn't drive the truck till I killed the sounder. Beeeeeeeeeeep! AHHHHHH!