Peugot 406 auto windscreen wiper problem

If it is the same as my wife's now sold on 306, the sensor is mounted in the housing behind the interior rear view mirror. When the windscreen was replaced we started to have problems with the auto wipers and it transpired that the sensor was not fully secured against the glass. Investigation showed that it works by shining a light (you can see it from outside the car when the wipers are set to auto) from one side of the sensor which is picked up on the other side, an inch or so away, through the refraction of the glass. Rain on the window affects the refraction index and this is detected to start the wipers. More rain = more refraction change and the wipers respond by speeding up. After several attempts I did mange to get the sensor stuck well enough to operate but the earlier attempts showed just how pernickety it could be. Sorry, but I can't remember how I stuck it in the end. If you want to get to it the mirror and housing slide up to remove them. Watch out that you don't trap wires when replacing it (sudden thought, maybe someone did)

Thanks Tinkerer that's a great help. Jogey

For what it is worth, I never saw that message on our 406 (not a HDi which we ran for about 8 years - we now have a 407 - HDi). Your experience resembles ours after we had to replace the 406 windscreen. The interesting post, which describes how 'auto' works, probably points to the conclusion (which is that you will have to put up with your auto until you replace your 406 - hardly a major problem).