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2020 Mustang GT Alarm Problems

  • Thread starter Thread starter attiladomonkos71
  • Start date Start date Apr 4, 2021
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    5.0 alarm ford mustang gt problems
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attiladomonkos71

New Member
Apr 4, 2021
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Hungary
Apr 4, 2021
#1
  • Apr 4, 2021
  • #1
Hi,

I bought a brand new 2020 Ford Mustang GT in February. Thirty days went by without any problems, I drove 1200 miles. The car was always kept in a dark, safe and locked garage.
After thirty days, the car’s alarm suddenly went off, without any external input (I wasn’t even in the garage). After about 20 seconds the alarm stopped. I noticed that only the siren sounded, without the horn and the hazard lights. This was strange, but I first thought that something triggered the interior alarm. So as an experiment, I rolled down the windows, locked the car with the remote, then moved my hand in the interior. As expected, the alarm went off, but with the horn and the hazard lights (not only the siren, as before).
After a week, the story repeated itself: the siren went off in the locked garage, then 20 sec later it stopped. (Again without the hazard lights and the horn, only the siren). This time I got there faster, so I could see that neither of the information panels showed anything.
I got the advice, that maybe the battery had low voltage, and that caused the alarm. So I measured the voltage, but it was perfect. (The fact, that 30 minutes before the second alarm I had a 100 miles long road trip with the car without any problem, proves that the battery functions well).
I am absolutely clueless, because as mentioned before, the car didn’t give any feedback in connection with the alarms, and I can’t connect the cases to any external circumstances. The alarm system is the default one (which is in every Mustang), I didn’t modify or buy anything to it.
Obviously I went to the Ford salon (Hungary) where I bought my pony, but the dealer couldn’t tell me what the problem could be. Since the problem isn’t something I can show him whenever I want, he couldn’t help.
So I’d be overjoyed if anyone could help me how to solve this problem, perhaps, (if my case is unprecedented) how can I deactivate the alarm system, which is quite useless for me, because I always keep my car in a locked, safe garage, and I never leave my car where it could be stolen.
 

Qwk88LX

Member
Dec 1, 2003
202
21
19
Sunrise, FL
Apr 26, 2021
#2
  • Apr 26, 2021
  • #2
attiladomonkos71 said:
Hi,

I bought a brand new 2020 Ford Mustang GT in February. Thirty days went by without any problems, I drove 1200 miles. The car was always kept in a dark, safe and locked garage.
After thirty days, the car’s alarm suddenly went off, without any external input (I wasn’t even in the garage). After about 20 seconds the alarm stopped. I noticed that only the siren sounded, without the horn and the hazard lights. This was strange, but I first thought that something triggered the interior alarm. So as an experiment, I rolled down the windows, locked the car with the remote, then moved my hand in the interior. As expected, the alarm went off, but with the horn and the hazard lights (not only the siren, as before).
After a week, the story repeated itself: the siren went off in the locked garage, then 20 sec later it stopped. (Again without the hazard lights and the horn, only the siren). This time I got there faster, so I could see that neither of the information panels showed anything.
I got the advice, that maybe the battery had low voltage, and that caused the alarm. So I measured the voltage, but it was perfect. (The fact, that 30 minutes before the second alarm I had a 100 miles long road trip with the car without any problem, proves that the battery functions well).
I am absolutely clueless, because as mentioned before, the car didn’t give any feedback in connection with the alarms, and I can’t connect the cases to any external circumstances. The alarm system is the default one (which is in every Mustang), I didn’t modify or buy anything to it.
Obviously I went to the Ford salon (Hungary) where I bought my pony, but the dealer couldn’t tell me what the problem could be. Since the problem isn’t something I can show him whenever I want, he couldn’t help.
So I’d be overjoyed if anyone could help me how to solve this problem, perhaps, (if my case is unprecedented) how can I deactivate the alarm system, which is quite useless for me, because I always keep my car in a locked, safe garage, and I never leave my car where it could be stolen.
Click to expand...
That's really odd. I would say setup a camera in your garage, but it doesn't sound like this occurs that often. Hopefully not a small animal residing in your car somewhere lol.. or a ghost
 
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