Xantia automatic wipers (Pah! Who wants them anyway?)

Sl4yer · Post by **Sl4yer** » 19 May 2009, 17:16

The wipers on the Activa have worked 'Intermittent' instead of 'Auto' since I got it. The sensor wasn't well fixed to the windscreen, but I noticed that the 'receiving' window was covered in glue, presumably in an effort to fix it better.

Yesterday, I obtained a 'new' sensor from Ebay. On plugging it in and switching to Auto, I saw that the LED on this one was on continuously, and it controlled the wiper speed as would be expected (fast when held away from the window, slow when pressed to the window, etc.). The old sensor would make no difference to the wiper speed at all, and the LED flickered rather than being on continuously.

Got some sticky pads today, only to find that the new sensor is now behaving exactly the same as the old sensor! Flickering LED, no wiper control. So either it just happens to have failed the same way the old one did, the car has made it fail in some way, or something else is wrong.

Any ideas?

James

DickieG · Post by **DickieG** » 19 May 2009, 18:17

The sticky pad you're using is too thick, to get around this issue use as thin a pad as you can find then pack foam/bubble wrap into the recess on the mirror mount to press the sensor against the screen. Citroën dealers do sell the pads separately @ about £7.

Sl4yer · Post by **Sl4yer** » 19 May 2009, 18:20

It may be that the pads are too thick, but the thing I don't get is that it worked yesterday held on my hand!

James

JamesQB · Post by **JamesQB** » 19 May 2009, 19:20

Not a bad connection with the wiring is it? Maybe the movement caused it to work and then play up again?

Sl4yer · Post by **Sl4yer** » 19 May 2009, 19:44

JamesQB wrote:Not a bad connection with the wiring is it? Maybe the movement caused it to work and then play up again?

I did consider that. Might dig out the wiring diagrams.

James

DickieG · Post by **DickieG** » 19 May 2009, 21:23

The reason I made mention of the pad thickness is because I had the same problem on my HDi, when I compared that sensor with the one on my V6 it became apparent that the sensor must be pressed hard against the screen to the extent that the clear plastic in the centre of the sensor is compressed into the screen, alongside it is not sufficient. Since I replaced the screen with a new genuine Citroën screen which had the lugs already fitted the problem has been resolved.

Sl4yer · Post by **Sl4yer** » 27 May 2009, 21:16

Well, Richard is on the right track as always. I haven't got the sensor fixed on yet, but I have discovered that the flickering LED is some sort of self-test mode. When the Auto wipers are first selected, the LED flickers until the receiving side gets a reflection. Then, the LED is constantly illuminated and wipers operate automatically.

For anyone interested in how the sensor works, see the Bosch guide here.

James