How to disable alarm on 1997 F150?

How to re-disable car alarm after battery change

• How can I re-disable the alarm on my 1997 Ford Ranger, which came back to life after a battery change? I have a 1997 Ford Ranger. I recently had the battery replaced, and now the alarm, which previously was in some kind of permanently disabled state ("valet mode", maybe), has come back to life. (I don't have a remote/key fob for the alarm.) There are two alarm-related controls under the dashboard: a push button and a metal switch. There's also an LED on the dashboard giving some feedback. Currently, what happens is, at some point after parking the car, the alarm arms itself. When I open the door with the key, the alarm triggers. (I unplugged the siren speaker under the hood, so I've eliminated that part of the problem, at least.) I'm able to cancel the alarm by turning the key to the accessory position and pushing the push button under the dashboard. This cancels the alarm, and it stays off for "a while" after the car is parked (which, strangely, can vary from minutes to hours), but eventually it rearms itself. I'm not sure what effect the switch has. When I turn it one way, the LED blinks twice; the other way the LED stays off. Either way, the alarm will still rearm itself. I believe that before, when the alarm was in permanent disable/valet mode, the LED stayed on solid. Now it's either off (during the temporary cancel after pushing the push button), or blinking (armed). So, I'm wondering what the best approach is from here. Is there a magic combination of button presses/switch toggles to get it back into disabled/valet mode? I looked up some alarm manuals, but I couldn't find one that matched exactly enough to be useful. Can I find a better manual by finding the alarm model somewhere? Or should I try to buy one of those generic remotes online? Or maybe just take it to an alarm shop? As far as the history: my Dad bought this car new, but doesn't know much about the alarm. He thinks it was an aftermarket item installed by the dealer as some kind of promotion. Since he didn't really want it, he just told them to leave it in but disable it, I guess. He doesn't have a remote/key fob and doesn't remember ever having had one. The owner's manual for the car doesn't refer to any alarm option. Thanks for any help.

• Answer:

  Probably not the most helpful response, but my 1998 Ford Explorer had nearly the exact same problem, same circumstances. The alarm had been disabled by the previous owner, obviously, but I couldn't figure out how to re-do what they did after changing the battery. After months of attempts to fix it myself, I eventually took the car to the Ford dealer and had them unplug the whole alarm system for something like $100.