Ford Mustang Mach-E Alarm Going Off? (16 Main Causes)

The Ford Mustang Mach-E is a stylish all-electric vehicle.

It comes loaded with features and tech although it can have alarm issues.

If your Mustang Mach-E’s alarm keeps going off, this article is here to help.

Why Does My Ford Mustang Mach-E Alarm Keep Going Off?

A Ford Mustang Mach-E alarm is usually triggered by a faulty door switch or hood switch. Other common causes include internal motion sensors detecting bugs, outdated software, 12V battery issues, key fob issues and a corrupted door sensor module. 

1. Malfunctioning Door Switches

Faulty door switches (including the rear hatch) are a common cause of random alarms on the Mustang Mach-E, these switches monitor the open/closed status of the door – if damaged, faulty or dirty they can send false readings thereby triggering the alarm.

Door switches are a common point of failure as they are subject to wear and tear due to the doors being continually opened/closed/slammed etc.

The door latches and door switches can get dirty too which can cause issues, so the first thing you should do is give all door latches a good clean and spray some WD-40 on the latch and work it in to see if that helps.

Also check the wiring leading from the body into the door for any signs of damage, it should be in a flexible hose on the hinge side of the door.

If you suspect the alarm issues are linked to the door switch, ask your dealer to run a diagnostic test to try and pinpoint the fault.

“I haven’t had SecuriAlert turned on in a long time. I believe it tells you the specific door, right? If it is the same door every time you likely have a faulty door latch.” – MachEForum.com

2. Faulty Hood Switch

A faulty hood switch is a common cause of unwanted alarms for Ford vehicles (Mustang Mach-E included).

The switch is typically embedded in the hood latch.

The small electronic device is designed to detect whether the hood is open or shut and is an important part of the car’s alarm system – if it is broken, loose or dirty it can send false readings to the car’s computer thus triggering the alarm.

  • Pop the hood and locate the hood switch.
  • Check for any obvious damage, rust or loose connections.
  • Give the hood switch a clean too (use contact cleaner), as dirt and grime can cause issues.
  • You can test the switch with a continuity tester.

If you are well-versed mechanically, you can buy a new hood switch online and replace it yourself. Otherwise, we’d advise visiting your local mechanic.

Related: How Long Will a Ford Mustang Mach-E Last? (Complete Guide)

3. Internal Motion Sensor

A common cause of the Mach-E alarm going off is linked to the interior motion sensors.

The idea behind these is that it lets you keep your window open – but the alarm will go off if someone reaches in your car to steal something.

Sometimes insects and bugs might get trapped in the car or even leaves being blown in, which can be picked up by these sensors thereby triggering the alarm.

If you have left your dog in the car, then they can also trigger the internal sensors.

If you suspect the issue is linked to the internal sensors, try disabling them for a week and spray some bug spray in the cabin too.

“Are your interior motion sensors on? One night my alarm went off several times during the night (I slept through it, but my Nest camera caught it…..woke up to motion alerts in my Nest app from the flashing lights). Turns out a moth got into my car when I came home that night and every time it would fly around, it would set off the alarm…” – Reddit.com/r/MachE

What Does The Manual Say?

You can select two levels of alarm security, All Sensors and Perimeter Sensing.

All Sensors

All sensors is the standard setting – In all sensors, all equipped sensors are on when you arm the alarm.

Note: Do not arm the alarm with all sensors if passengers, animals or other moving objects are inside your vehicle.

Perimeter Sensing

In perimeter sensing, the interior sensors are off when you arm the alarm. All the other equipped sensors activate when you arm the alarm in this mode.

Setting the Alarm Security Level

Access the vehicle drawer on the touchscreen.

  1. Press SETTINGS.
  2. Press Vehicle.
  3. Press Alarm System.
  4. Press Motion sensors.
  5. Press a setting.

Ask on Exit

You can choose which level of security you require after you switch the ignition off.

Note: If you do not choose a setting, the system defaults to all sensors.

Switching Ask on Exit On and Off

Access the vehicle drawer on the touchscreen.

  1. Press SETTINGS.
  2. Press Vehicle.
  3. Press Alarm System.
  4. Press Ask on Exit.
  5. Press a setting.

4. Outdated Software

Vehicles that are as technologically sophisticated as the Mustang Mach-E are dependent on constant firmware and software updates. 

If you fail to update your vehicle’s software packages, you may encounter random errors and glitches, including the car’s alarm going off.

The solution for this is simple: always update your vehicle’s software modules to prevent any bugs, glitches, or errors. 

A couple of owners on MachEForum.com shared the following:

“I had some bugs that were easily solved with a software update at the dealers…”

“I put tape over my interior motion sensors to remedy this issue in the short term. I recently took off the tape because I had all of my software modules updated in my car. The alarm hasn’t gone off anymore. Definitely go to a dealer and have them take a look at it and do some updates and/or replace some defective hardware.”

5. Corrupted Door Sensor Module

A very specific software issue that is constantly brought up in forums is a faulty door sensor module update.

To have this resolved, owners must report to the nearest dealership immediately to downgrade the software version of the door sensors to a more stable (reliable) state.

One owner on the r/MustangMachE subreddit mentioned this:

“This is a known issue where the door sensor is corrupted. Contact your dealer for repair.”

6. Drained 12V Battery

A faulty or weakened car battery causes a variety of problems, including accidentally triggering the Mustang Mach-E alarm.

The best thing to do is take your Mustang Mach-E for a battery health check, these are usually quite inexpensive or sometimes free such as at AutoZone.

Or you can test it yourself with a multimeter (see the guide at the end of this article).

A healthy 12V battery should be about 12.6 to 12.8 volts while a weakened battery reads below 12 volts.

7. Loose or Bad 12V Battery Connections

Loose or bad 12V battery connections can cause a number of problems, including triggering the alarm of your Mustang Mach-E.

A bad connection can be caused by dirt or gunk buildup.

The terminals may have come loose from driving and vibrations etc.

Make sure the engine is off before doing any work on the battery.

  1. Inspect the battery and look for any signs of damage, dirt build-up, rust, or corrosion.
  2. Disconnect the battery and loosen the nuts on the clamps using a wrench.
  3. Remove the negative clamp, marked with a “-” first.
  4. Clean the terminals with a toothbrush dipped in a mix of baking soda and water, rinse with distilled water and dry with a cloth.

Reconnect the battery, ensuring tight connections.

8. Faulty Key Fob

Another reported cause of nuisance alarms on the Mustang Mach-E is a faulty key fob – it may be damaged or require reprogramming.

If you have 2 remotes, try taking the battery out of one and use the other for a while.

If the alarm problems persist, and you have tried cleaning the inside of the fob(s) and changing the battery, the best thing to do is speak with your dealer.

9. Key Fob Running on Low Battery

A common cause of mysterious alarms on the Mustang Mach-E is a low key fob battery. Similarly, if the fob is dirty or dusty this can also cause alarm issues.

Give the inside of your fob a clean and replace the battery to eliminate this possible cause. It’s worth spending a bit extra for a good brand of battery.

  • To open your key fob, stick your prying tool into the slit or gap between the two halves of the outer casing and gently apply upward pressure to pop open the device.
  • Remove the battery.
  • Give the key fob a good clean to remove any dirt or fluff – a cotton swab and some rubbing alcohol should do the trick.
  • Check for damage, rust or loose connection (you may need a new key fob depending on what you find).
  • Be sure to insert the new battery facing the right way up.
  • Assemble the outer casing of your key fob by clamping them back together.

10. Accidentally Triggering the Key Fob’s Panic Button

It is not uncommon for owners to unintentionally activate the panic alarm of the Mustang Mach-E.

While a lot of owners have chalked it up to poor key fob design, a few others have attributed unintentional triggering to other objects in the same pocket as the key fob. 

An easy fix for this is to have a dedicated pocket for your key fob, free from any other objects (such as pens or house keys). 

11. Incorrectly Installed Aftermarket Alarm

An incorrectly installed or faulty aftermarket alarm system is a common cause of nuisance alarms.

Aftermarket alarms are typically far more complex than any factory-installed equipment which makes them more prone to issues.

They may also have been installed by incompetent individuals.

If you are experiencing issues with an aftermarket alarm, the best thing to do is speak with a reputable auto electrician.

12. Wind and Vibration

The Ford Mustang Mach-E’s alarm sensors can be quite sensitive. Excessive wind or vibration can trip the alarm quite easily, according to reports online.

To deal with the wind, make sure all doors and windows are shut tight. 

As for the vibration, keep your Mustang Mach-E away from roads or highways when parked.

13. Rust and Corrosion on Door and Hood Latches

Rust and corrosion can also damage the latches and switches, which may trick the sensors into detecting that a door or the front hood is open.

If your car is frequently exposed to moisture or other external elements, then you should routinely inspect critical areas of your vehicle for any sign of rust or corrosion. 

14. Damaged Wiring

Damaged electrical wiring can cause a wide range of problems, it can often be tricky to pinpoint too and you may need to have an auto electrician run some diagnostic tests.

Related: Ford Mustang Mach-E Beeping? (19 Causes & Solutions)

15. Animals Climbing On The Vehicle

If your alarm has been set off in the middle of the night, it may have been by an animal climbing on the car.

States such as Illinois, Indiana, Iowa, Texas, Wisconsin, and Carolina have large wild raccoon populations. 

Have a look for footprints on the hood and the roof. 

If you have a CCTV system, examine the footage. These animals usually appear during the night. 

16. Not Closing Doors, Hood, or Trunk Properly

Something as simple as not properly closing the doors, hood, or trunk will inevitably trigger the alarm.

Make sure to check if you have closed every point of entry of your vehicle to avoid accidentally tripping your Mustang Mach-E’s alarm. 

Alternative Suggestions

Check for Recalls or TSBs

By entering your car’s VIN number on Ford’s recall page or the NTHSA’s Safety Issues & Recalls page you can determine whether or not there is a TSB or recall for your vehicle and if there is you’ll want to get it addressed.

A recall is issued by a vehicle manufacturer for issues that are safety-related, while a TSB covers components that may be malfunctioning but don’t compromise the safety of the vehicle.

Disconnect the Battery

Sometimes mysterious alarm problems can disappear with a simple reboot, there are no guarantees here but it’s worth a try.

Disconnect the battery for 20 seconds and this resets many of the electronics in the vehicle.

Check For Warning Messages

When the alarm occurs can you see any lights or warning messages on the instrument panel?

This can give a clue as to what’s causing the alarm e.g. ‘Hood Ajar’.

Take it to a Ford Dealership

If needed, take your Ford to the dealership.

Tell them you are NOT paying for a check on what the problem might be.

Ask them if they will check it for free.

Most dealerships and other places do quick/initial diagnosis for no money as they plan to make money for the repair of your vehicle.

If your unit is still under warranty then they should fix and resolve the issue for free.

How to Test the 12V Battery

How to Test the Battery:

  • Before testing, remove the surface charge from the battery, this allows for an accurate reading.
  • Simply turn on the headlights for 2 minutes then turn off.
  • Set the multimeter dial to the ’20 Volts’ setting.
  • Make sure the car is turned OFF.

The multimeter will have a red probe and a black probe.

  • The red probe is for making contact with the positive terminal.
  • The black probe is for making contact with the negative terminal.

Measure across the battery terminals.

  • The meter should display a reading, if the battery is fully charged the voltage should be between 12.2 and 12.6 volts.
  • Anything under 12V and the battery should be charged or replaced.

Sources

https://www.ford.com/support/owner-manuals/

https://www.ford.com/support/recalls/

https://www.fordservicecontent.com/Ford_Content/Catalog/owner_information/2021-Ford-Mustang-Mach-E-Owners-Manual-version-1_om_EN-US_09_2020-1.pdf

Author:

  • Ian Sawyer

    Growing up with a father who was a mechanic I had an appreciation for cars and motorcycles from an early age. I shared my first bike with my brother that had little more than a 40cc engine but it opened up a world of excitement for me, I was hooked. As I grew older I progressed onto bigger bikes and...

    View all posts