How to Adjust a Car Alarm

by Dianne Christensen-Herman

Car alarms can provide an ideal way to protect your vehicle and any valuable belongings contained inside. However, if you set the alarm's sensitivity too high, it may become a hassle more than a convenience. If your car alarm is triggered unnecessarily such as when you slam a car door or a cat jumps on the hood, you may want to turn down the sensitivity. You can complete this process with a few basic tools.

Step 1

Locate the shock sensor, usually beneath the driver-side dashboard. It should look like a small black or clear box about 3 square inches in diameter.

Step 2

Search for the adjustment dial -- a small dial or inset screw located along one side of the module. Turn the dial clockwise with either your fingers or the tip of a slotted screwdriver to turn up the sensitivity; turn it counterclockwise to decrease the sensitivity.

Gently slap various areas of the vehicle with a flat hand with fingers spread to test the sensor; remove any rings from your fingers before performing this step to avoid damaging your car. Test the sensitivity at the four corners of the vehicle. Adjust the alarm's sensitivity again if needed.


  • A vehicle's alarm shock sensors only respond to vibration and impact. Do not kick the tires or push on the car to test the sensitivity. Most alarms come equipped with a "dual stage" sensor that lets out a short chirp for light impacts and emits the full siren on heavier impacts; keep this sensor in mind while performing the adjustment
  • .
  • The exact location of the shock sensor depends on where the installer placed it. Usually, the module is secured to a bundle of wires with wire ties. If the sensor is not easily accessible from beneath the dash, you may have disassemble some of your vehicle. Begin by removing the knee bolster, or the panel below the steering column. The tools and process will depend on the type of vehicle. If the process appears complicated to reach the shock sensor, contact a professional for assistance.

Items you will need

  • Screwdriver and socket set

More Articles