Hi all.

Just recently the intermittent wipe on my 2018 Fiesta has begun acting oddly.

When I switch the wipers to intermittent they always start off with one wipe and then a fairly long pause before the next one, and in the past they have self-adjusted to the nature of the rain. But the last week or so they have gradually gone faster and faster until they're on really fast wipe speed, even though the rain is not falling all that heavily. (In this condition I can put the stalk up a notch to standard wipe, and the wipers actually slow down rather than speed up.)

If I switch the wipers off completely when they're doing this they resume with the long pauses initially, but then start getting faster and faster once again.

I sort of suspect the rain sensor may be giving the system erroneous information about the rain, but I'm not sure where that is or how it works. Is there any sort of maintenance one can give it? Other than that, my best guess is the system computer going haywire, but I have no idea how to address that. Is there anything one can do to do the equivalent of the old 'switch it off and then back on again' trick?

Change your wiper blades and ensure the rain sensor is clean on the windscreen.

Adjust the sensitivity on the wiper stalk 

Thanks Dave.

 

Forgot to mention that adjusting the sensitivity on the stalk seemed to have no effect whatever; the wipers just went at full speed regardless.

Blades seem okay to me with no streaking or anything, but is it still possible that they need to be changed for the sensor?

And I believe the sensor is in front of the rear-view mirror, which I have checked, and it does seem clean but I will give the screen exterior at that point a bit of scrub.

Yes, with rain sensor, the wipers only have to degrade a bit and leave a small amount of water on the sensor and the wipers go do-lally

Right, thanks again. Off to Halfords in the morning, then.

I have exactly the same problem you describe with my Ford Galaxy,  in first 'up' position (intermittent wipes) it does start off with one normal paced wipe, then a pause, then faster and faster until its the fastest speed it can go, until I manually stop this pace, by pulling the wiper stalk back down to 'off', or putting higher up to 'constant wipe' position.  the various speed/sensitivity settings dial set in the wiper stalk, makes no difference to the wiping speed when its at 'intermittent' wipe mode, and all positions of the dial don't change the speed .... anyone know what I might need to d to get it fixed so as the wiper stalk wheel actually controls the pace of wipe again?  thanks in advance.....