Hey there. I've got a '98 f150 Supercab XLT 4X4. Every so often, and even more often here lately, my alarm goes off for no apparent reason. I can just turn off the truck ignition, take the key out and the alarm goes off. Also, I have gotten out of the truck, set the alarm and walked away. By the time I get about 10-15 feet away, the alarm goes off. It has also happened in the middle of the night; NOT FUN!!!! There really doesn't seem to be any common thing happening to cause it, just random times. WTF?!? Thanks in advance!

 

Is it a factory installation or an aftermarket?

If aftermarket (most likely), you'll have to take to a technician who can ientify the system and diagnose it for you.

If I had to hazard a guess, I'd start with the DOOR AJAR switches.

Steve

 

My bad, should've stated "factory". I have the factory key-fob, and the idiot light on the dash that says "theft"(I think).

 

Any ideas? PLEASE????

 

I had that happen once...told me my keyless entry pad was shot...replaced it, never had a problem.

 

Good advice.

 

my 1998 f150 is at the dealer right now getting the same problem fixed,they just call me back and told me that i needed a new battery!! i guess the old one was getting weaker and made the alarm go off.

I hope this helps.

 

Truck battery or key-fob battery? As to the key-pad, I don't have the key-pad type of keyless, only the key-fob. What and where are the door ajar switches? If they were messed up, wouldn't the door ajar idiot light come on?
Also, my door chime rings constantly, even though I've thoroughly drenched them with WD-40. Could I have a key switch problem causing all of this? It seems that sometimes, if I jiggle the key switch just right, it quits beeping. I'm definitely stumped... And thanks for the answers already given.
Eric