Where is the vehicle longitudinal acceleration sensor located?
2 Answers
Longitudinal acceleration sensors typically do not have a fixed position. In most vehicle models, they are installed near the front of the vehicle's center of gravity. Of course, a single vehicle may have multiple longitudinal acceleration sensors, such as on the wheels or B-pillars. Their function is to detect the phenomenon of vehicle lift or dive during acceleration or braking, in order to control the adjustment of ADS damping force on the front and rear axles, thereby providing optimal ride comfort. Below is the working principle of acceleration sensors: 1. The sensing element converts the acceleration signal at the measurement point into a corresponding electrical signal, which enters the preamplifier circuit. After signal conditioning to improve the signal-to-noise ratio, it undergoes analog-to-digital conversion to obtain a digital signal, which is then sent to a computer for data storage and display. 2. Automotive acceleration sensors operate on the principle that an object's inertial coefficient generates varying pressures under different accelerations, using different resistances to distinguish between different acceleration levels. Vehicle body acceleration sensors are primarily used in ABS systems and airbags.
I often work on cars and find that the longitudinal acceleration sensor placement is quite particular. It's usually installed near the center of gravity in the middle of the vehicle body, such as along the central tunnel of the chassis, under the front seats, or near the trunk floor. This design ensures accurate detection of longitudinal acceleration, with minimal signal interference from vehicle pitching. Connected to the onboard computer, if damaged, it can affect safety functions like ABS and electronic stability control. Once I found one under the underbody panel of a German car—just a small black box bolted in place. Locations can vary significantly between models, so it's best to consult the repair manual or inspect under the chassis directly. Always disconnect the battery before removal.
