UPDATED February 10, 2022 This piece has been updated to reflect the emergence of new technology

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Christian Mathews Security Writer

Car alarms are necessary to protect your vehicle from theft or vandalism. Among the many types of car alarms, aftermarket alarms are quite popular and convenient since they can be controlled remotely. We’ll be showing you how to reset aftermarket car alarms, should you run into any problems with them.

You activate or deactivate these alarms with a key fob. Once the alarm is activated, the vehicle emits sounds or flashlights when anyone, including you, touches it. These days, most aftermarket alarms alter the internal circuit of the car. So when triggered, it doesn’t allow the car to start.

Of course, all these features are essential for the safety of your vehicle. But there are many cases when you might need to reset your car’s aftermarket alarm manually. If you damage or lose the key fob and the alarms are still active, you can’t get your vehicle started.

It’s not something that happens frequently, but knowing how to reset the alarm will keep you prepared for such situations.

So in today’s post, we have listed various ways to reset your car’s aftermarket alarm. Especially in case, the key fob is no longer working or accessible. For extra security while on the road, why not consider a Dash Camera for your car.

Why Should You Know How to Reset Aftermarket Car Alarm?

Whether your key fob is damaged or lost, if you can’t deactivate the car alarm then you can’t operate the vehicle. In such a situation, you will probably need to call a mechanic to turn off the alarm. Push start button kit.

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If you know how to do it, you will be saving money that you would otherwise pay mechanics to do. It’s a handy thing to know for tight situations when you suddenly lose or misplace the alarm remote. This is especially true if you need to get in the vehicle urgently. Having said that, let’s see the different ways to reset your car’s aftermarket alarm.

Ways to Reset a Car’s Aftermarket Alarm

By Activating the Valet Switch

A valet switch is a button that turns off the security functions of a vehicle. This switch is not immediately visible, and in most cars, it’s located somewhere below the car’s dashboard. So to deactivate your alarm, you need to follow just a few quick steps.

  •  First, locate the valet switch on your vehicle. Some cars may not have a valet switch. So check the car manual to confirm whether your car has this switch or not.
  • After you have found the valet switch, don’t press it right away. First, use the keys of your car to turn it to the ‘ignition on position. Since the alarm is active, turning the key won’t start your vehicle, but you still need to keep the keys in an on position to use the valet switch.
  • Now, you can turn on your valet switch, and it will immediately deactivate the car’s alarm system. But keep in mind that as long as the switch stays on, the alarm will remain disabled. That’s why it’s important not to forget it in that position. Once you have managed to get the remote, turn off the valet switch again. If you forget to turn off the valet switch, you will be leaving your vehicle unprotected.

Disconnecting and Reconnecting the Car Battery

The next way to reset your car alarm is to disconnect the car’s battery. This cuts off the electric supply before reconnecting it again. It requires a bit more effort than the previous method. However, the advantage is that using this method, you can turn off the triggered alarm while still keeping the security system active.

For this method, you must follow these steps:

  • Find the battery of your car under the hood and disconnect the ground cable. If you don’t know which is the ground cable, it’s the one that connects to the negative terminal of the battery. As soon as you disconnect the ground cable, it will cut off the power supply to the car. So any horns, sounds, or flashing lights will stop.
  • Now with no power supply in your vehicle, you need to lock all the car doors manually. Lock all doors from the inside and the driver seat door from the outside using your key.
  • After that, you need to manually press down the hood position detector of your car. It’s a small upward-facing switch under the hood and stays pressed as long as the hood is closed. We can’t close the hood yet as we need to recommend the cables to the battery. Press the hood post detector manually to make the car system think that the hood is closed when you restore the power.
  • Reconnect the ground cable to the battery and restore the power supply. Once you restore the power, the alarm system will also be active. However, the alarm will no longer be in the triggered state. Finally, you can close the hood.
  • Keep in mind that the idea behind this method is simple – resetting the alarm by turning the power off and back on. When we restore the power, we want the car’s security system to believe that the vehicle is untampered with, so it won’t trigger the alarm again.

That’s why we locked all doors and kept the hood position detector closed before restoring power. It makes the alarm system think the vehicle is untouched.


So the next time you find your car’s alarm blaring and can’t seem to find the alarm remote anywhere, you don’t need to panic. Now you do not need to spend some bucks hiring a mechanic to fix the problem. Now you know how to reset the aftermarket car alarm. Using either one of the two methods above, you can easily do that.

The valet switch method is convenient. However, it may not always be an option since not all cars have a valet switch. The second option can be used on all vehicles. Ensure you use safety precautions when disconnecting and reconnecting the cables though.