factory alarm malfunction

[signal7]

Hey guys, I'm new here but have been lurking for about two years. I've just never joined or posted. I have a CW 96 cobra with 35,500 miles( I also own a 2011 GT premium with 1,300 miles). I bought the car this past June to use as my DD. The car is stock other than 98 cobra wheels, radio, crap shocks/struts, shorty antenna, tint, and cobra front grill emblem.

On to my problem. I've noticed about once a month or so the alarm/horn will randomly start going off. I always use the factory key fob to lock the car. I cannot get the alarm/horn to go off unless I open the door and put the key in the ignition to the on position or start the car, can't remember which one. The car has never had a problem starting after alarm activation. The theft light will be blinking. I turn the alarm off, get out of the car, and lock the car with the fob again. The alarm always goes off again within 30 seconds to 15 minutes. It will do this a few times during each episode but then will be fine for another month or so.

I have googled/searched this forum and others for this problem and found many posts with my exact problem but no replies that are pertinent or contain a fix or solution. Any help is appreciated.

 

[98$vt]

Welcome! i wish my car was cw with low miles. Anyway, Lmao mine was doing this last winter. Kept going off at 1-3am waking up all my neighbors and stuff. The problem I had was the little push sensor thing that turns off the dome light when you shut the door was broken on the drivers side. Not sure exactly why it was doing it but after I replaced both sides just to be sure I never had the problem ever again

 

[signal7]

Well, I left the car unlocked last night because it would not stop going off. This morning I went out and locked it and sure enough the damn thing starts going off. This time I was able to shut it off with the fob as I was walking up to it. So I got in the vehicle and locked it with the fob again and 30 seconds later it's going off. The theft light in the dash stays blinking with the ignition turned to the on or start position. All the manual states when this occurs is take the vehicle in for service. Of coarse, why didn't I think of that.:idea::dw: The light does go off when i actually start the car.

98$vt, thanks for the reply. Would your interior dome come on or the open door chime activate when driving around? I ask because mine doesn't but would be an obvious indicator of a faulty switch. When you replaced the door plunger switch did you have to remove the door panels or do they remove by just taking off that large nut on the exterior door jam side.

Also, are their any other switches that would make this system go off, like a trunk switch. I looked at the trunk and didn't see any plunger type switch. I think I remember reading somewhere about a grey wire on the trunk latch that might be related to the system but what do you do with that? Could it possibly be a faulty control module and if so where is that located. I'm also going to replace the key fob batteries today to eliminate this possible problem.

Anybody else?

 

[Mr.Bolt-on]

HAHA!!! My dads 1996 GT did this all the time. You'd be in the parkinglot walking away from the car after it's been electronically locked. Then it starts going off for no reason... extremely embarrassing.

That alarm system had a mind of its own. So no, you are not alone, and yes it brings back wonderful memories of being careful not to wake the alarm.

 

[98$vt]

Well, I left the car unlocked last night because it would not stop going off. This morning I went out and locked it and sure enough the damn thing starts going off. This time I was able to shut it off with the fob as I was walking up to it. So I got in the vehicle and locked it with the fob again and 30 seconds later it's going off. The theft light in the dash stays blinking with the ignition turned to the on or start position. All the manual states when this occurs is take the vehicle in for service. Of coarse, why didn't I think of that.:idea::dw: The light does go off when i actually start the car.

98$vt, thanks for the reply. Would your interior dome come on or the open door chime activate when driving around? I ask because mine doesn't but would be an obvious indicator of a faulty switch. When you replaced the door plunger switch did you have to remove the door panels or do they remove by just taking off that large nut on the exterior door jam side.

Also, are their any other switches that would make this system go off, like a trunk switch. I looked at the trunk and didn't see any plunger type switch. I think I remember reading somewhere about a grey wire on the trunk latch that might be related to the system but what do you do with that? Could it possibly be a faulty control module and if so where is that located. I'm also going to replace the key fob batteries today to eliminate this possible problem.

Anybody else?

The guy before me basically disconnected everything in my car on the drivers side so the door doesn't chime the seat belt doesn't blink or chime and the dome light doesn't come on when the drivers door is open
But anyhow the plunger you can get to with the door open it takes only a min, mine was being a pain just like you say and that's the only thing that fixed it. My switch was busted tho so it made an impression on the car that the door was always open

It was doing something else funny also I just can't think what it is right now :bash:

 

[signal7]

I brought the car to the Ford dealer today thinking I would just order the plunger part in the doors like 98$vt suggested. I spoke to the mechanic there that is familiar with these older cars and systems and he stated the door plunger is not related to the anti-theft system. He stated their is a switch in the latch mechanisms in the doors, trunk, and possibly the hood. He stated he could plug into the OBD port and be able to pull up something like the last eight times it went off and what triggered it. He said he would then have to trace it from there and maybe pull the door panels and check wires and connections. He also stated he has seen the module go bad in another customers car and he had to rebuild it as the part is no longer able to be ordered for replacement. Got a quote from the service writer and was told maybe $300. Uggh. I'll be dropping it off tomorrow morning.

Anyways, any other info or advice I could use or pass along would still be helpful. I'll update the findings and report back.

 

[Wynn]

This will sound crazy but put your key and fob on the dash above the radio. Hold it there a while (couple minutes).

Sounds nuts. Once I put my g/f's ford truck key in the Cobra's ignition, and the car acted up and wouldnt start after that due to a PATS issue. Held the key to the dash because I read it somewhere online. I was definitely skeptical but it actually worked. No guarantees, but give it a try.

 

[wvragtop]

ok please let us know what it is hope i never have the issue but good to know a fix

 

[signal7]

This will sound crazy but put your key and fob on the dash above the radio. Hold it there a while (couple minutes).

Sounds nuts. Once I put my g/f's ford truck key in the Cobra's ignition, and the car acted up and wouldnt start after that due to a PATS issue. Held the key to the dash because I read it somewhere online. I was definitely skeptical but it actually worked. No guarantees, but give it a try.

I could see that happening if you attempted to use the wrong key, but I've never had a problem starting the car, even when the alarm is acting up. But hey, it's easy enough it won't hurt to try. The problem is it does this at random so even if it works I most likely wouldn't know it unless I waited a few months to see if it happens again. Problem with that is I've got a toddler and neighbors have toddlers, and this damn thing always manages to go off randomly at night. I need to get it fixed so I can lock it and not worry about waking up the neighborhood.

ok please let us know what it is hope i never have the issue but good to know a fix

I definitely will do that.

Also, I had the batteries in both fobs replaced today and the car battery tested, it's fine. Had this done to eliminate these two possible issues for the cause.

 

[signal7]

Well I dropped off the car at 9:00 this morning for a 9:15 appointment. They said they would need the car for a few hours and would call me when they figured something out. I ran around town doing errands and what not and then decided to go back to the dealership even though I hadn't heard anything yet. I got back to the dealership at 1:45 in the afternoon. I saw the mechanic as I was walking up and asked him what they found out. He replied he hasn't looked at the car yet because they put a few other cars before mine because the customers were waiting. WTF, Why have an appointment? I was told nothing was booked for this mechanic for the time when I made an appointment. I personally don't care if another customer is "waiting." I'm "waiting" too, just not at the dealership. I thought I made an appointment to minimize my waiting. When I dropped off the car I explained I would be running around on that side of town just burning up time and would be back early afternoon. Sorry for the rant, just wasted a day.

They pulled the car into the bay about 2:00 and started work. About 2:30 I walked over and asked the mechanic what codes were showing for the alarm and he advised no codes are available regarding anti-theft as this was not available on 1996's. I don't think these type codes are available until 1998 but I'm not 100% sure about that. I asked if they locked the car while it was sitting there all morning to see if it would maybe go off and of course it wasn't. They messed with the car trying to get it to go off, act up, or go off on it's own without success. I waited around until 4:00 and decided to check the progress. They said they would need more time to come up with a diagnosis and asked if they could keep the car overnight. I asked how they would bill for this and was told it's a flat rate of $110 for the diagnosis and we would go from there depending on parts and labor. Maybe I'll have better luck tomorrow. I'll update when I know more.

 

[gnatsumarboc03]

This thread is funny, my 96 gt did the same thing it would always go off, so I always locked the doors manually fixed the problem haha.

 

[98$vt]

Stealer dealer

 

[deadernie]

I've got the same problem as the OP although mine is a '98. I need to get it to the dealer to see if they can find where the malfunction is coming from. In the research I've done I've see people say that the problem turned into a total immobilization and had to get towed.

 

[signal7]

Picked the car up from the dealer today. I was looking through paper work regarding the cobra and ran across the original window sticker. The options listed PREFERRED EQUIPMENT PKG.250A and includes the CD player, Mach 460 sound sys, ANI-THEFT SYSTEM, and leather seating surface sport buckets. So I got to thinking, if the anti-theft is an option it should be able to be bypassed. I called the dealership and asked my service rep to run this by the mechanic and see what he thought. He called me back and told me they have not been able to determine the fault in the system. He stated the mechanic advised this would be the best option because he could completely bypass the anti-theft fairly easily versus possibly having another problem down the road. When I picked up the car the mechanic had the wiring diagram and told me he had to splice some wires and tie into something but electrical work is like speaking another language to me and I don't understand it. I was assured all other functions of the car would not be affected, and they haven't so far. The mechanic stated he has had to do it on other customers vehicles. I'm thinking WTF, why wasn't this suggested before when I was discussing the problem with him. I could have avoided the diagnostic fee which told me nothing, still don't know what was actually wrong with it. Anyways, It's done now and the bill came to $225. Sorry this doesn't help with anybody else who might have a problem other than it can be bypassed but I don't know what that included.