The GMC Acadia is an attractive midsize SUV.
Like many other vehicles, this model is vulnerable to alarm-related problems.
If your Acadia’s alarm keeps going off, this article should have the answers you need.
Table of Contents
Why Does My GMC Acadia Alarm Keep Going Off?
An GMC Acadia alarm is typically triggered by faulty door switches. Other common causes include a defective hood switch, a damaged 12V battery, and a faulty key fob.
1. Faulty Door Switches (Sensors)
Door switches that are damaged or faulty can cause nuisance alarms by transmitting incorrect signals to the alarm system.
These switches, also known as sensors, are prone to wear and tear from the frequent opening, closing, and slamming of doors, with the driver’s door experiencing the highest level of wear.
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.
Inspect the wiring that runs from the car’s body to the door for any signs of damage. Typically, this wiring is enclosed within a flexible hose located on the door’s hinge side.
If you have concerns that the alarm issues could be linked to the door switch, it’s advisable to ask your dealer to conduct a diagnostic test to pinpoint the problem.
2. Faulty Hood Switch
Similar to the door switch, a faulty hood switch can result in nuisance alarm activations.
Typically, this switch is incorporated within the hood latch mechanism.
This small but essential electronic device plays a critical role in the car’s alarm system by detecting whether the hood is open or closed.
Damage, looseness, or dirt accumulation in the switch can result in incorrect signals being sent to the vehicle’s computer, which in turn can activate the alarm unnecessarily.
- Open the hood and locate the hood switch.
- Check for any clear signs of damage, rust or loose connections.
- Give the hood switch a thorough cleaning (with contact cleaner), as dirt and grime can cause issues.
- You can test the switch with a continuity tester.
If you’re mechanically inclined, consider purchasing a new hood switch online and installing it yourself. Otherwise, it’s recommended to seek help from a local mechanic.
Related: 11 Most Common GMC Acadia Problems (Explained)
3. Drained 12V Battery
A depleted car battery can cause various problems, such as accidental alarm triggering.
It is recommended to have your battery tested for its condition, a service that is often inexpensive or complimentary at locations like AutoZone.
Alternatively, you can conduct a self-assessment using a multimeter (refer to the guide at the end of the article below).
Typically, a functioning 12V battery should register between 12.6 and 12.8 volts, whereas a failing one will show below 12 volts.
Some GMC owners have reported alarm problems, which have been attributed to the battery not having enough power in cold weather.
4. Loose or Bad 12V Battery Connections
Incorrect or insecure links to the 12V battery can result in different problems, such as the unintended activation of your Acadia’s alarm system.
These connections often accumulate dirt or corrosion over time.
The vibrations from regular driving can cause the battery terminals to become loose.
Always make sure to turn off the engine before conducting any battery maintenance.
Adhere to the following basic steps if you intend to conduct the assessment on your own:
- Examine the battery for any indications of wear, such as dirt, rust, or corrosion.
- Detach the battery, starting by loosening the clamp nuts with a wrench.
- Always disconnect the negative clamp, identified by a ‘-’ sign, first.
- Use a toothbrush soaked in a baking soda and water solution to clean the terminals. Rinse with distilled water and dry thoroughly.
- When reconnecting the battery, make sure the connections are secure and tight.
“May want to check for cracked battery. We had this problem the winter 2020. couldn’t find problem gave it back. The next day same thing happened 45 miles from dealeship… Fine line crack at the bottom of the battery. Replaced battery no more problem. Just a thought.” – AcadiaForum.com
5. Key Fob Running on Low Battery
Sometimes, alarms go off unexpectedly because the key fob has a low battery. Also, if the fob is dirty, it can cause similar issues.
To fix these problems, clean your key fob inside and put in a new battery. It’s usually better to use a good-quality 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.
“Try changing the RKE transmitter (fob) battery. It may be getting weak. A lot of strange intermittent things can happen when the transmitter battery gets run down.” – AcadiaForum.net
6. Faulty Key Fob
Another reported cause of nuisance alarms on this vehicle is a faulty key fob.
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.
7. Incorrectly Installed Aftermarket Alarm and Accessories
Incorrect installation or defects in an aftermarket alarm system or accessory are frequent sources of bothersome false 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.
8. 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.
In some instances, rodents may have chewed through an electrical wire.
9. Water Damage
Exposure to water or moisture can occasionally result in short circuits or corrosion in the electrical wiring, resulting in issues with the alarm system.
Identifying water damage in a vehicle’s electrical system can be complex and often necessitates a professional, such as an auto electrician, to perform diagnostic tests to pinpoint the issue.
10. 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 vehicle.
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.
11. 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 vehicle’s alarm.
Alternative Suggestions
Check for Recalls or TSBs
By entering your car’s VIN number on GMC’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 an GMC Dealership
If needed, take your GMC 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://cdn.dealereprocess.org/cdn/servicemanuals/gmc/2022-acadia.pdf
- https://www.gmc.com/ownercenter/recalls
