When door mirror heating is selected does the heating stay on for a specific time (i.e. similar to the rear widow heating) or does it have to be turned off, if you remember!? It's probably not a good idea to leave the heating on for too long. The manual only says to turn the heating off by moving the switch to another setting.

2 minutes ago, bertJ said:

When door mirror heating is selected does the heating stay on for a specific time (i.e. similar to the rear widow heating) or does it have to be turned off, if you remember!? It's probably not a good idea to leave the heating on for too long. The manual only says to turn the heating off by moving the switch to another setting.

In my 2014 Rapid it says on until I turn it off. Ditto all my previous Skodas. Personally I just leave it on and it's never been a problem. It also helps to clear spray from the mirrors in wet conditions.

There has been some discussion about this on the BRISKODA forum relating to earlier Fabia models and plenty more discussion on VW-related forums.

The Fabia Mk4 Owner's Manual explains how to use the exterior-mirrors' control-switch, with the switch's heating position just described as "Heating the mirrors with the engine running (to switch off the heating, select a different position of the control)".

Similar guidance is in my 2009 Skoda Roomster's Owner's Manual, saying that mirror heating only takes place when the car's engine is running. No mention is made of a 'time-out' period.

I've always assumed that the mirror heating has no finite time limit after which heating ceases and, when I've driven long duration journeys in persistent wet weather and turned on the mirror heating at the start of the trip, I've never seen any evidence of the mirror-heating stopping. (it's certainly the case that, if the exterior mirrors' control-switch is left in the heating position, every time the car's engine is started, mirror-heating will resume.)

(My last motorhome (Fiat Ducato based) had a single dedicated On/Off switch for rear window/exterior mirrors heating. The switch had a tell-tale light and - when heating had been selected - after 10 minutes heating stopped and the light went out.)

Yes, I'd heard of several VW mirrors dropping out apparently because of melted glue caused by too long use of mirror heating. It's probably a matter of some doubt! I also had a Toyota where the rear window and mirror heating were combined in one switch and turned off after a few minutes. It seems that it doesn't really matter how long you leave the mirror heating on Skoda's

I've referred back to the Owner's Manual of my Fiat Ducato=based motorhome (that I sold in 2021). The guidance about heating the vehicle's rear window and its exterior mirrors is comprehensive, saying that heating of the window AND mirrors involves pressing a single dashboard 'heating' button and that window/mirrors heating automatically stops after 20 minutes.

The Owner's Manual of the 2021 Hyundai i20 car that preceded my current Fabia Mk4 explains how to turn on the rear-window heating (button on dashboard) adding that the heating automatically stops after 20 minutes. The fact that doing this simultaneously causes the exterior mirrors to be heated is not mentioned anywhere in the Manual (though it soon becomes apparent when driving in wet weather that it happens). Mirror-heating was regularly asked about on Hyundai forums by buyers of new i20 cars.

The Fabia Mk4 Manual has a section on "Windows heating".

Advice on rear-window heating (press the appropriate dashboard button) does not mention any 'time-out' period.

Advice on front windscreen heating (press the appropriate dashboard button) says "Windscreen heating switches off automatically after a certain period. If the engine is switched off when the heating is on and turned back on again within about 10 minutes, heating resumes". This suggests (to me) that the 'time-out' period is roughly 10 minutes.

14 hours ago, bertJ said:

Yes, I'd heard of several VW mirrors dropping out apparently because of melted glue caused by too long use of mirror heating. It's probably a matter of some doubt! I also had a Toyota where the rear window and mirror heating were combined in one switch and turned off after a few minutes. It seems that it doesn't really matter how long you leave the mirror heating on Skoda's

I have a friend that has a 2019 Audi A6 and he reported that his driver's side mirror glass did "fall off" - and it sounded like his "helpful" garage fitted a new glass on - and he was surprised that the mirror heater no longer works! I explained that a new suitable mirror complete with heater tape and backing plastic frame should have been fitted to sort that out and still have a heated mirror - which he finds that he needs.

Just a word of warning maybe, when I moved from having a VX Cav GSI 4X4 (it had heated mirrors connected to the timed rear window heater) to a new 2000 VW Passat 4Motion that had "winter pack", I stupidly left the heated mirror switch on - always, then read on a USA Passat forum about people having burned out the heaters on their mirrors by doing that, by this time I did notice that the heaters were now not as effective as they had been originally - and yes, both mirror heaters had burned out the resistance between the heater terminals had become quite high and was now just the charred remains on the heater tape backing strip! That cost quite a bit to buy 2 new heated mirrors, I didn't repeat that trick of leaving mirror heaters on, although, the other day I did notice that the heaters on my wife's Polo were switched on, hopefully they have survived and that was my fault!

There is evidence that it is possible on certain Skoda models to use VCDS or OBDeleven to alter the length of time that rear-window heating or exterior-mirrors heating continues. For example, these links relate to earlier Fabia vehicles.

https://obdeleven.com/customizations/skoda/fabia/2007-2010/mirror-heating-time?srsltid=AfmBOoo148qAbmFUv7cdKyLN-ucGlFGCCI8idkyzllpvR09mmpBHYsFf

https://www.briskoda.net/forums/topic/78661-timer-for-heated-mirrors/

My 2024 Fabia's Owner's Manual warns "Risk of getting burned! Do not touch the heated exterior mirror glass." So, logically, if the glass can get that hot, it's best not to have mirror-heating turned on unless it's actually needed.

When I turn on my Fabia's or Roomster's rear-window heating, the button that does this is (reasonably) visible and this 'encourages' me to turn off the heating when it's no longer required.

That's not the case with exterior-mirrors heating: the control can easily be left in its heating position and there's no 'encouragement' to move it. As has been observed many times, if it were more apparent when the control was in its heating position (eg. a little LED on the control) the chances of leaving the heating on unnecessarily would be minimised.