Chevrolet Silverado 1500 Alarm Going Off? (9 Simple Causes)

The Chevy Silverado 1500 is one of America’s best-selling light-duty trucks.

But like any other vehicle, it’s not uncommon for the alarm to go off at random.

If you’re Silverado alarm keeps going off this article is here to help.

Why Does My Chevrolet Silverado Alarm Keep Going Off?

A Chevy Silverado 1500 alarm is often triggered by a faulty hood latch sensor. Other causes include key fob issues, a failing 12V battery, sticking latches, faulty sensors, and issues with wiring and electronics.

1. Faulty Hood Latch Sensor

A very common cause of the alarm going off on the Chevrolet Silverado is a faulty hood latch sensor.

Otherwise known as a hood switch, the component is a simple electrical switch that reports the state of the hood.

When the alarm is armed, the hood should be closed and the switch confirms this by closing its circuit.

Due to their location at the front of the vehicle, hood latch sensors often get dirty and clogged up so it’s worth giving it a clean and some lubrication first.

You may even notice a “Hood Open” warning, if the hood is closed, then this often means you need a new hood latch.

If you suspect the hood switch is faulty and your truck is under warranty, you should be able to have it replaced by your dealer for free.

If you’re mechanically inclined you can replace it yourself, otherwise you can expect to pay around $200 for a new hood sensor.

2. Key Fob Issues

A faulty key fob can cause problems with the alarm system. Try using a replacement key fob to see if the alarm problems stop. Its also a good idea to open the fob and give it a good clean as dirt and debris build up can have a negative impact on the electronics.

If you suspect your fob is broken you can also ask your local dealer to repair it, which should work out cheaper than buying a new one.

Similarly, if your Silverado has a low key fob battery this can trigger the alarm to go off at random too.

Try using your spare coded key – if the problem goes away then you know you’ll need to replace the battery in your primary key fob (or even the fob itelf).

Avoid carrying big metal objects, electronics or a second coded key on the same keyring as your primary key fob as this can cause problems too.

3. Failing 12V Battery

A 12V battery that is failing or has insufficient voltage can cause a wide range of problems, including causing the alarm to go off at random.

If you’ve had the battery for more than 4 years it may be time for a new one or it may just need to be properly charged.

The first thing you should do is test the battery.

You can do this yourself with a voltmeter, we’ve included a step-by-step guide at the bottom of the article, the battery should not have less than 12V.

Alternatively, take it to your dealer or local AutoZone who should be able to do a battery test free of charge.

It is also recommended that you give the battery terminals a good clean using a toothbrush dipped in a baking soda and water mixture and ensure the terminals are tight and free from gunk, debris, corrosion and dirt.

If your Silverado has rusted battery terminals it will be unable to deliver the correct electrical power to various parts of the truck.

4. Faulty Door Lock Sensors & Sticking Latches

A faulty door latch sensor is a common cause of Silverado alarms going off.

Similar to the hood latch sensor, your Silverado alarm monitors the doors to make sure no one is opening them.

Give all door latches a clean and some lubrication with WD-40.

A latch that is sticking can also trigger the alarm.

Here’s what one Silverado owner had to say:

“Today I picked up some contact cleaner and sprayed the crap out of the latch, cleaned all the grease, oil, whatever out of it then sprayed penetrating oil in the latch… It looks good so far, it seems the cleaner worked or the penetrating spray worked”

Related: Chevrolet Silverado Beeping? (7 Common Causes)

5. Faulty Body Control Module

A common reason why a Silverado alarm keeps going off is due to a faulty body control module.

The body control module or ‘body computer’ is the electronic control unit responsible for monitoring and controlling various systems associated with the vehicle’s body such as the alarm, immobilizers, power windows etc.

The body control module can develop corrosion on the pins or connections can become loose.

Other common symptoms of a bad BCM include:

  1. Repeated battery drain
  2. Starting problems
  3. Erratic electrical functions e.g. horn, wipers, lights, lights on the dash
  4. Security and alarm system problems

6. Damaged Wiring

Damaged electrical wiring can cause a wide range of problems.

Wiring damage can occur from general wear and tear or even from rodents chewing on the wiring.

Broken wires aren’t easy to find and you’ll need to have an auto electrician carry out some basic tests on your vehicle.

A common point of failure for electrical wiring is in and around the doors.

7. Incorrect Installation of a New Alarm

If you have recently had a new alarm fitted and it’s going off at random, then there’s a good chance it was installed incorrectly.

Your best option is to go back to the mechanic who installed it and explain your problem.

8. Aftermarket Alarms

If the car has an aftermarket alarm fitted (one that did not come as standard with the vehicle) then this may have been incorrectly installed.

It may also have overly sensitive sensors which can be triggered by strong wind or even a cat or dog.

These alarm systems are often more sophisticated than a basic factory-installed car alarm but are often installed by people who aren’t mechanics.

If you have an aftermarket alarm that’s causing you problems it’s best to have it examined by a trained auto electrician.

9. High Voltage Power Lines

Parking underneath overhead power lines can trigger the alarm on your Chevrolet Silverado.

This phenomenon is caused by electromagnetic radiation (EMR) which can interfere with the electronics on your alarm system.

If you suspect this is the cause, simply park somewhere else out the way.

Depending on where you live this may not be relevant as power lines can often be located underground.

What Does the Manual Say?

The inclination sensor can set off the alarm if it senses movement of the vehicle, such as a change in vehicle orientation.

The intrusion sensor monitors the vehicle interior, and can activate the alarm if it senses unauthorized entry into the vehicle’s interior.

Do not allow passengers or pets to remain in the vehicle when the intrusion sensor is activated.

Before arming the theft-deterrent system and activating the intrusion sensor:

  • Make sure all doors and windows are completely closed.
  • Secure any loose items such as sunshades.
  • Make sure there are no
  • obstructions blocking the sensors in the front overhead console.
  • Close DVD screens, if equipped, before leaving the vehicle

Inclination and Intrusion Sensors Disable Switch

It is recommended that the intrusion and inclination sensors be deactivated if pets are left in the vehicle or if the vehicle is being transported.

With the vehicle turned off, press o in the front overhead console.

The indicator light will come on momentarily, indicating that these sensors have been disabled for the next alarm system arming cycle.

Source: https://ownersmanuals2.com/chevrolet/silverado-1500-2018-owners-manual-77252/page-47

Alternative Suggestions

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 Chevrolet Dealership

If needed, take your Chevrolet 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 you’re Chevrolet is still under warranty then they should fix and resolve the issue for free.

Related: 21 Best & Worst Chevrolet Silverado 1500 Years (Explained)

Check for Recalls or TSBs:

By entering your car’s VIN number on Chevrolet’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.

Pull the Horn Fuse

Is your horn the alarm on your security system?

If so, pull the horn fuse.

That should keep it from going off all hours of the day and night.

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.

Resources

https://www.chevrolet.com/bypass/pcf/gma-content-api/resources/sites/GMA/content/staging/MANUALS/5000/MA5633/en_US/2.0/22_CHEV_Silverado_1500_OM_en_US_U_84719634B_2022APR04_2P.pdf

https://www.chevrolet.com/bypass/pcf/gma-content-api/resources/sites/GMA/content/staging/MANUALS/4000/MA4988/en_US/2.0/20_CHEV_Silverado_OM_en_US_U_84186886C_2020JAN30_3P.pdf

12 Common Chevrolet Silverado 1500 Problems (Explained)