PetrolDave

Checked the relevant fuse? If that's OK then as said I suspect the water may have caused the motor to rust internally and fail.

The washer supply runs through the motor and it's not unknown for this to cause the motor to fail - I had it happen on my previous car.

My understanding is that VAG consider anything less than a litre every 1000 miles to be "normal". That's what was said to many other owners of my previous car (an RS4) when they complained of a litre every 2000 miles or so.

The suffix letter is the version number, generally the higher the letter the newer it is. There are at least 4 sellers of the G version, take your pick...

.. or a hair dryer?

That's what I normally do, but I also like 'belt & braces' so I have 2 Skoda SD cards!

The navigation database part number 5E0051236E is for a MIB1 Amunsen map database on an SD card - you should find this SD card in one of the SD card slots in the glovebox unit. With an Amundsen you must use a genuine SD/VW SD card as they have a special 'CID' so any other SD card won't be recognised as a map database. Another SD card is easy to find at much less than the dealer price, just search on an auction site for the part number 5E0051236 and get the latest one (there's currently a G version on eBay).

... and make sure to request that they activate Android Auto too.

Proximity spreads the fire, but the key word is "flamethrower" which strongly suggests some Li based batteries aggravated the fire.

Further digging into the circuit diagrams show 3 headlight options - Halogen, Bi-Xenon and Bi-Xenon with LED running lights. Choosing the right one shows the pinout is correct! Then looking into the adaptation channels of the BCM shows why a failed front sidelight is reported as rear left turn light - Skoda have got the dataset wrong and the output controlling the front sidelight is attached to Leuchte channels for the rear turn light!

I have Canton in my 2016 L&K hatch, the sub is completely within the box to the left of the boot leaving the spare wheel well completely empty - where I have a space saver spare, tools, and miscellaneous 'stuff'.

A recent thread by @toot showed the cost on a rapid charger as 79p/kWh, assuming 4miles/kWh that works out at 19.75p/mile. I average 45mpg in my 2016 1.8TSI Octavia and I most recently paid 150.7p/litre that works out at 15.15p/mile. So your comment is absolutely true when charging overnight at home (at 7p/kWh) but most certainly NOT true when having/choosing to use rapid chargers when away from home.

Sounds like VAG have messed up their diagnostics reporting - VCDS just reports what the VAG software says

I wish all the software bugs to be fixed!

While on holiday in south Devon the front nearside sidelight bulb failure warning would show on the Maxidot when the auto headlights turned on. I'm surprised that there's no 'cold monitoring' so the warning only shows when the bulb is turned on. Looking at the circuit diagram from erWin and comparing that with the Leuchte channels in the BCM shows different pin numbers on the BCM for the front sidelights? Can anyone shed some light on which BCM pins and Leuchte channels actually control the front sidelights with Bi-Xenon headlights?

Blown fuse Faulty wiring Power management disabling them due to poor battery state of charge You need a VAG specific code reader such as VCDS or OBDeleven, rather than a generic OBD reader, to see the detail.

A small but important point - it's not a "VCDS voltage", VCDS merely reports what the firmware in the VAG/Skoda module setting is.

This video explains that the valves stay closed when the cylinders are deactivated https://www.youtube.com/watch?v=yoohR8sar5g

You don't need a serial number on the battery, as @ApertureS said just change the serial number stored in the battery managment module by 1 digit.

I've made a similar change from a 1.4TSI to a 1.8TSI and observed the 1.8 coming out of ECO mode - but it's under situations where engine braking is required rather than just coasting , such as going down an incline (not even a hill).

Presumably you were able to drive it betweem January and July - in which case your local main dealer has caused the problem?

If you have Front Assist then you have ACC, disabling Front Assist does NOT disable the "Adaptive" part of Cruise Control - so it will continue to adapt its speed according to how close other cars are in front. That's how ACC works. Have you tried reducing the distance setting for ACC using the slider control on the top of the cruise stalk?

On the Octavia 3 that's the case, but some other models had the 1.4TSI ACT engine.

Both of my Octavia's (1.4TSI and 1.8TSI) have had the full battery cover, sides & top.

No, the instruments don't have the software in them to display a green dipped beam symbol - in their 'wisdom' many car manufacturers have removed it!