Rear wiper failed, front wipers puzzling

[triumphtigger]

I have a 2006 4x4 Octavia 2 (not a Scout). Yesterday I found that my rear wiper didn't work (it had stopped in the parked position). Later, when I pulled up at lights, the rear wiper did two intermittent wipes and I thought it was okay again. But I was wrong, it hasn't worked since then.

 

I have rain sensing wipers (front only, of course). I always leave the wiper switch in the sensing, intermittent wipe position. Today I used the washers, and the wipers came on like they should, but when the automatic wipes finished, the wipers stayed on intermittently, as if on timer. I had to flick the lever down to stop them.

 

The front wipers no longer respond to rain, only to the switch. When I switch to rain-sense position they do the timed auto wipe thing, the intervals dependant on the small switch that usually controls the sensitivity of the sensor.

 

I thought the rear wiper had failed, but it is clearly more complicated than that. The fuse is okay - and I can hear a relay click when I lift the stick to the rear wiper position. I'm convinced these two things (rear wiper failing and front intermittent wipe reverting to timer rather than sensor) are related in some way.

 

The only thing I have done recently (that may or may not be connected) is to set a speed warning for the long 40 limit over the Forth Road Bridge. I toggled the switch a few times because it's years since I used it. MFD came up accidentally, with the warning that I couldn't change settings unless stationary. Because I kept my eyes on the road I might have inadvertantly changed something? 

 

Any ideas please...

[silver1011]

The rear wiper is notoriously unreliable on the Octavia, mainly due to water ingress, although they usually randomly stop at any point along the sweep, not at the parked position.

 

Have the front wipers reverted back to intermittent? I wonder if the rain sensor fails they automatically default back to intermittent?

 

It could be switch related, if the issues only started after toggling the end button. Try wiggling the switch with the rear wiper turned on and see if it brings it back to life.

 

If all else fails it will be worth getting the car scanned using VCDS, the fault may have flagged up a fault code.

[SuperbTWM]

I presume you haven't been doing any changes with VCDS recently that could have changed the coding?

 

As Silver suggests the rain sensor may be faulty but before going any further it would be worth checking that the auto wiper function is enabled with VCDS and that there are no error codes for it. Just in case something strange has happened.

[triumphtigger]

Thanks for your replies, I have been away but will look at the car again when the rain stops!