1997 F150 Lariat. Anti-theft alarm started going off without cause. All cases are about 20 minutes after truck is shut off. Key in door stops the alarm, but did not fix the problem. Got about three different reasons and three different fixes from three different dealer's shops. Pulling fuse #13 in cab also kills the power windows and dome / map lights...not a option. How can I by-pass the system. Any advice out there?

 

In the drivers kick panel.............there will be wires coming in from the door panel through the boot in the door........

There is a green/with a purple stripe.......that is the disarm wire for the factory alarm, take that wire and "ground it", that will take care of your problem FOREVER!

It works........trust me. When I do remote starts, they usually trip the OEM alarm....either that or the add on keyless trips it so I have the make the add on features throw a "ground" to that wire so they work with the OEM alarm.

However, as I stated above.......just put a "ground" to that wire and ............BAM.........problem solved.

GOOD LUCK.

Let me know how it goes.

 

Husker F150:

Tried as you said. Hope I got the correct wire. Bundle just behind the drivers side kick plate, goes into a gang terminal of about 16-20 wites. Grounded to truck. Just did it, so will see if it alarms tonight. Noticed that now the "Brake" light on the dash is on while the ignition is on. Any thoughts? Seems like every circuit is dual function.

Thanks for your help,

Skogman.

 

you may have not tagged the correct wire.............

Also make sure that your E brake is fully depressed!


Otherwise try this.........do the same thing to this wire: pink/orange.............................. passengers kick panel


we'll get.....'er

 

Solved the problem, I think. On the drivers side kick plate, grounded a blue wire from the top row of the 16-20 gang terminal quick disconnect. Disabled the "theft" light icon on the dash board. Seemes to have solved the problem / disabled the alarm. It's been about 1.5 weeks, and all seems well. Thank's to Husker 150 for his (her) help! I will monitor this site for a few weeks incase any body has any questions or comments.

Skogman.

 

I thought that grounding that blue wire solved the problem. It did for a couple of weeks, but the alarm went off again the other day. So even though the grounding killed the dash icon, the alarm apparently is still up and running. Must have been by chance that it did not alarm in the last couple of weeks.

 

I think I'm going to stay with my first idea.....................ground the Dark Green with a purple stripe wire, this wire is coming in from the door boot you should be able to find this wire in the drivers kick panel. If you cannot find it there, you may have to grab this wire inside the actual door boot, then run a extra wire to it and and ground that wire inside the truck.

The Dk. Green w/ purple stripe wire comes from inside the door, this wire is connected to the lock cylinder on the door, so when you "unlock" your door with a key, by doing so the lock cylinder turns and throws a "ground" to the DK Green/purple wire and thus disarming the OEM alarm. I'm 100% positive this will solve your problem, if not, your LARIAT is haunted and I would consult a specialist in PARANORMAL activity.

GOOD LUCK>

 

most of the time it's the hood sw. just a tought. easy to check. good luck. sounds like your into this thing pretty far. hope all is good.

 

you know what. i'm wrong. i was thinking of a tarus that's what i get for thinking. hehe. sorry.

 

I am assuming you have a factory-installed alarm, not one installed by the dealership or an aftermarket installer. For a 97 F150, the Remote Anti-theft Personality module performs this feature.

Chances are the problem is due to a faulty driver or passenger door ajar switch or the hood switch. Have you nocticed anything else strange like the domelamp staying on or the door ajar indicator staying on - the door ajar switches have been known to act up (just do a search on this board).

It will cost some $ but any dealership can hook up their diagnostic tool to your truck and determine the last 8 events that set off your alarm (i.e. driver door, pass. door, hood, PANIC, ignition tamper, etc). This should pinpoint your problem very quickly.

Worst case, there is a pin on the RAP that you can ground to shut the alarm system off. If you want to pursue this I can provide more information.

 

Buschman:

Yes it is factory. Yes, I am VERY interested in knowing what pin on the RAP, its location. I plan to attack this problem ASAP. Any info would be greatly appreciated. One year ago the dome light / door ajar icon used to stay on, but dealer told me to spray WD40 in latch in door, this solved that problem. I suspect a similar event going on with the switch, or a faulty component in the circuit. The door ajar and dome light are not a problem now, there for I question if that same switch is the problem or not. I located what I think is the RAP module on fire wall, to left of steering wheel, about 3" x 5". I found a dark green w/ purple stripe wire going into it. I plan to ground this wire, assuming it is the same one that HuskerF150 is talking about. Is this the same one you are thinking about?

Thanks

 

Yup - HuskerF150 is correct. Let us know if that does not solve your problem.

Just make sure you have the Dark Green with Purple stripe (Disarm) and NOT the Light Green with Purple stripe (Starter Interrupt).

 

Got a question......I have a 2000 F150 SuperCab 4X4 I just picked up about 6 weeks ago......when I turn off the ignition, all of a sudden there's a red THEFT light blinking on the dash......is this really some sort of security device or is it just a placebo? I have to pick up an owner's manual on this thing, as the Chilton's I got for it doesn't have any remark about it. Thanks for any input.

 

On your 2000 F150 the LED is not for an alarm system but for the PATS system (the coded key system) - it is basically telling you it is 'armed' and will not allow the vehicle to start until you insert the proper key.

 

FYI:

Per my 08/30/2002 post:

I grounded that wire, and all seems well. The alarm has not sounded since then. Thanks for all the help.