I have a 1998 V8 with an extended cab with some starting issues. I bought it last August with some break issues at 252K miles. Since then I've fixed the breaks and put about 5500 more miles on it. Engine runs great. The theft light is solid and it won't crank or start, just a clicking in the direction of the radio. Now the only way I can start it is to turn the key to the "on" position and jump the starter solenoid. Starts every time like that. Also the alarm is really finicky and will go off even if all I did was open the door. I have two keys: one original ford (with S stamp) and one aftermarket. Truck has a brand new battery. Theft light is always on even when I drive it around. Any help would be appreciated.

 

List what was broke so we can get a better idea of what you're dealing with.

 

The theft light originally came on I after fixed the continuous door ringing issue (the little contact point inside the ignition cylinder was always touching so I bent it back to normal). After I put it back together the alarm came on. Leaving the key in the ignition, in the "on" position for 3 to 4 minutes cleared the theft light and it ran normal for several weeks. I took it on a long trip and then things started to freak out on me. When I parked it after about 300 miles I came back to the truck and the alarm came on just from unlocking and opening the passenger door. I did get the light to go out and it started up. But on the return 300 miles the theft light slowly came on while driving. Since then I've had intermittent issues where it wouldn't start or the alarm would sound just from an open door.

 

Update:
I left the battery off last night and pulled the ECU relay. It seemed to reset everything and when I initially put the key to try starting it, there was no theft light. I cranked it and it started right up. But after 2 to 3 seconds the light came on solid again. Right now it seems if I don't arm the system by locking the doors I never have any issues (except a solid theft light). If I do lock it the alarm will come on when I unlock and open the door. For now I'm just glad it starts up.

 

Wait. Did you mean "brakes" vs "breaks"? That makes more sense.

 

Eats, shoots, and leaves.

 

Well I can see that was very confusing. Yes I fixed the brakes. That was the only drivability issue when I bought it. I'll try to stop talking like a caveman.

 

Just having fun.

Is your alarm system the Ford factory system or some sort of aftermarket unit? Doesn't sound like PATS. PATS doesn't need arming.

Whatever it is it seems to be dying. Best figure it out while you can still use the truck. Happy New Year.

 

A 98 won't have PATS. It sounds like the OP's truck has the optional rudimentary perimeter security system that was incorporated into the RAP module. When triggered (door lock cylinder switch, not to be confused with the door ajar switches, or the ignition cylinder anti- tamper switch), it flashes the lights, blows the horn and disables the starter via an interrupt relay.

Sounds like you may have mucked up the ignition anti-tamper switch circuit while you were in there.

[Edited 1/1/23 to ad some details, italicized above]

 

Everything seems to be factory. The only thing I've noticed that's not is the aftermarket key.

Ignition anti-tamper switch sounds about right. The first time I ever had issues was when I pulled the ignition lock cylinder out. Big mistake. I'd take the door chiming any day over this. Is there a part I replace to get it back to normal? Or a way to reprogram the keys? Everything I've read on that front seems to be related to PATS, which as you said, I don't think this is.