XM wiper stalk end-button

[Old-Guy]

Slow, wet and windy trip down the M5 yesterday. Discovered that the button on the end of the RH stalk doesn't appear to do anything; I instinctively expected it to be single wipe (IIRC like Xantia?). The rain stopped briefly before Brent Knoll services so stopped a comfort break and a quick check of the Handbook; couldn't find any mention of the stalk end-button, but it's not the correct Handbook (a bit older than the car: 1999MY V6 Exclusive).

This (wet and windy) morning; looking at p. 72 of the wiring diagrams, the only momentary switch I can see is wash-wipe (pull stalk back).

IIRC, there were several different versions of the RH stalk for the Xantia, perhaps the XM's stalk has been replaced. I seem to remember upgrading our Green Xantia (1995MY 1.9SX estate

Should it do something non-obvious and unrelated to wash-wipe (Cruise has it's own stalk).
Another electrical gremlin to sort?

Can anyone tell me what the end-button should do, please?

[PaulC5]

A google search came up with this
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The button on the end of the wiper stalk in a Citroën XM controls the trip computer (on higher-spec models like VSX or Exclusive) to toggle through telemetry data and readouts on the central display, or functions as a basic clock/temperature selector depending on the trim level.
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Telemetry data means the trip computer pages.

[Richard_C]

Never had an XM - wish I had - but I've owned a few Citroens with stalk buttons that do nothing. Maybe they come out of a standard 'parts bin' and its cheaper to fit it as-is.

The Aston Martin V8 has Austin Maxi doorhandles

[Old-Guy]

Thanks you both for that bit of vital information. So no flick-wipe

Tomorrow (when the rain has hopefully stopped) - I'll go and get the Handbook out of the car and look for the Trip Computer Section (if it has one!). The LH display has several blank/black lines, and the LH one is fairly dim so I generally don't bother with them.

Original (proper) Land-Rover Defenders have Morris Marina/Ital window-winders, instrument panel and switch-gear. The first time I drove a nearly-new one in the noughties, it was like stepping back to the '70s - though a Marina was a nicer drive than a Defender with All Terrain tyres on the M5! Ear Defenders advisable

[Paul-R]

The Aston Martin V8 has Austin Maxi doorhandles

As the Maxi was designed around Austin/Morris "Landcrab" doors surely that should read as such?

[Old-Guy]

Much more 'Landcrab' than just the doors. A versatile design, with hydro-pneumatic suspension too, but ruined by the truly dire transmission with an overhung pinion driving the diff crown-wheel. The 1750s were notorious for snapping them off if the clutch was dropped suddenly in 1st: Bang! Car rolls gently into the middle of the junction as the engine revs madly My wife had to learn to "double de-crunch" down-shifts, I learnt to drive aged 16 (off-road) on a Series 1 Landy only a year younger than my 16 years - I don't think synchromesh had been invented by 1949.