Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Side Impact Sensor
The side impact sensors in the vehicle are used to measure the mechanical stresses that occur in the event of a collision.
The four sensors which are used in the car are:
- 1 side impact sensor in each left and right B post
- 1 side impact sensor in each left and right door.
The side impact sensors in the B-post are acceleration sensors while the side impact sensors in the doors are pressure sensors. The sensors transmit data continuously to the control module. In the event of a collision, the control module uses the acceleration and pressure data from the sensors, and the control module's internal sensors to determine if the collision severity is enough to activate the side impact protection system.
Only the side impact protection system on the collision side is activated.
In the event of a fault in the side impact sensor, the control module stores a diagnostic trouble code (DTC). A diagnostic trouble code (DTC) is also stored if the communication between the control module and one of the side impact sensors does not function. Each side impact sensor has a serial number. The serial number is used to check that the correct side impact sensor is installed.
If one (or several) of the side impact sensors stops functioning, the control module uses the remaining sensor to determine when the collision protection should be activated.
The side impact sensors in the B-posts are the same and can be installed on the left or right side, but cannot be used in the doors. The side impact sensors in the doors are also the same and can be either installed in the left or right door.
Data is transmitted on the same cable used for power supply. There is a signal/power supply cable to each side impact sensor and a ground lead.
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.
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