how do you change the rear wheel sensor on a peugeot 307

the rear wheel sensors are typically a magnetic signal generating sensor that pulses an electric wave each time a spoke on the toothed ring passes through the magnetic field.

that sensor is typically bolted to the backing plate of the rear wheel above the toothed ring. typically there is only one bolt that holds it in' remove the bolt and the sensor should pull right out.

l seem to remember that you have to remove the brake caliper and brake disc. When you have done that there is a allen key head type bolt to remove (this holds the sensor in place) which is quite difficult to get at. The sensor slides out towards the front of the car. The sensor has a long delicate looking finger which fits by the wheel bearing. You will probably need to clean the rust from the area to allow the sensor to locate easily( using minimum force).