Acceleration Sensor, Body
There are three different acceleration sensors on the car body; two front ones and one rear one.
The front ones are at the front edge of the wheel housings behind each front lamp.
The rear one is on the floor in the luggage compartment in front of the left tail lamp in the S80. In the V70/XC70 it is on the floor in the luggage compartment to the right of the spare wheel well.
The acceleration sensors are supplied with 5 V from the Suspension module (SUM). The output signal from each sensor, when the vehicle is stationary, is 2 V.
During vertical acceleration movements, the signal oscillates around that value; the greater the acceleration, the greater the deviation. Information about the body's acceleration is used together with signals from the wheel's height sensor of the control module to calculate the damping in each shock absorber.
The acceleration sensors are diagnosed by the Suspension module (SUM).
It is important that the acceleration sensors are securely installed with the connector turned in the correct direction. The front sensors must have their connectors turned downwards and the rear sensor connectors upwards. (Note that the sensors are not the same and have different P/Ns.) If an acceleration sensor is loose, the control module may receive incorrect values resulting in poorer vehicle driving characteristics.