Well I have always wondered how rain-sensing wipers work... and today I finally found out as it rained while I was driving my Stilo... they don't!
It reminds me of the whole idea of TV ratings (which I abhore) - statistics makes the assumption that if a test group of people watch certain TV programmes, the total number of viewers can be extrapolated.
Anyway this same principle is obviously being applied to a tiny sensor in the windscreen glass, which is supposed to be representative of the water falling over the whole windscreen. Hardly! What if there is a blob of water on the sensor and lots everywhere else, or the same blob and hardly any rain elsewhere...
I think possibly another factor, since the sensor lies within the wiped area, is when the droplets are broken up into tiny drops by the wipers... The blades are in good condition and the glass looks clean, but I wonder if it may be suffering from a buildup of wash'n'wax or automatic carwash 'hot wax' (previous owner used carwashes, I don't).
Anyway, if you'd like more of the detail, I'd been leaving my wiper stalk at the first click. It started raining, and nothing happened, so I moved the stalk to 'off' and back to 'auto'. (Surely not very 'auto' if you have to turn it off/on each time it starts to rain?) There was a single wipe ("acquisition stroke", as the handbook calls it), and then a few seconds later, another wipe! Yes!!!
Then there was a wait of approx. 20 seconds (during which the screen was totally covered) and then a double-wipe. The interval now seemed to be only a couple of seconds, then there was some clicking and the wipers started on continuous, full-speed!
Things got really interesting as I approached a busy roundabout (well, with all the downchanging, indicators etc. busy for the CAN bus, at least). The wipers, which had settled down to one double-wipe every five, suddenly stopped altogether just as the rain set in harder. I could hardly see, but I thought that manually over-riding it would be cheating. I drove through anyway, hoping no-one was there (they weren't).
These cars have a lot of human character built in (and erratic Italian character at that ) I always thought that the 'Auto' mode of the Selespeed was like having a blindfolded passenger operating the clutch and gearlever. Now, I think Automatic Wipers are having the same blindfolded passenger operating the stalk, listening for the rainfall.
Cheers,
-Alex
It reminds me of the whole idea of TV ratings (which I abhore) - statistics makes the assumption that if a test group of people watch certain TV programmes, the total number of viewers can be extrapolated.
Anyway this same principle is obviously being applied to a tiny sensor in the windscreen glass, which is supposed to be representative of the water falling over the whole windscreen. Hardly! What if there is a blob of water on the sensor and lots everywhere else, or the same blob and hardly any rain elsewhere...
I think possibly another factor, since the sensor lies within the wiped area, is when the droplets are broken up into tiny drops by the wipers... The blades are in good condition and the glass looks clean, but I wonder if it may be suffering from a buildup of wash'n'wax or automatic carwash 'hot wax' (previous owner used carwashes, I don't).
Anyway, if you'd like more of the detail, I'd been leaving my wiper stalk at the first click. It started raining, and nothing happened, so I moved the stalk to 'off' and back to 'auto'. (Surely not very 'auto' if you have to turn it off/on each time it starts to rain?) There was a single wipe ("acquisition stroke", as the handbook calls it), and then a few seconds later, another wipe! Yes!!!
Then there was a wait of approx. 20 seconds (during which the screen was totally covered) and then a double-wipe. The interval now seemed to be only a couple of seconds, then there was some clicking and the wipers started on continuous, full-speed!
Things got really interesting as I approached a busy roundabout (well, with all the downchanging, indicators etc. busy for the CAN bus, at least). The wipers, which had settled down to one double-wipe every five, suddenly stopped altogether just as the rain set in harder. I could hardly see, but I thought that manually over-riding it would be cheating. I drove through anyway, hoping no-one was there (they weren't).
These cars have a lot of human character built in (and erratic Italian character at that ) I always thought that the 'Auto' mode of the Selespeed was like having a blindfolded passenger operating the clutch and gearlever. Now, I think Automatic Wipers are having the same blindfolded passenger operating the stalk, listening for the rainfall.
Cheers,
-Alex
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