Breezy_Pete

See some part number variants for the under-the-dash stuff here: LLLParts The parts with 0 as the third digit are common to both, but others where it's 1 or 2 are LHD/RHD specific.

Mirror image, yes.

https://www.lllparts.co.uk/catalogs/skoda/CZ

Try it again when the system is loaded enough that the voltage measured across the battery terminals is well under 14.2V, then repeat the voltage drop measurements. It will be interesting to see if the total of the voltage drops on each connection plus battery voltage add up to 14.2V or not. One of the small wires (the blue one) is the alternator excitation, only used for monitoring the output voltage after its initial function of booting up the alternator. It is self generated after this, once alt is spinning enough. The other is DFM, which is just information to the engine ECU about how much the alternator is 'trying' (the duty cycle of the regulator). Output voltage is fixed at the alternator +ve output terminal by the regulator, as long as the current demand is less than it is capable of supplying at that engine speed and full duty cycle.

With how much electrical load on the system at the time of these measurements?

Common story on lots of recent Skodas.

Nice, well done. Just a quick heads-up for UK or other readers where we drive on the left (RHD), the above link is for a LHD part, so unlikely to be suitable. RHD (6Q2) versions may be available there though, haven't looked.

I'd love to see some good evidence for this. What do you have?

Interesting. What part number are the new plugs, please? Fingers crossed that's all sorted now; good result. 👍

I think it's quite possible. Acidic vapour can come out of vents, and with bonnet down could go anywhere. Wiring damage may have occurred if any wires nearby had cracked insulation.

Never seen that word before but seems extremely appropriate to all sorts of car jobs! 😁

Don't know, sorry.

Did it have reflector or projector headlights? Might well make a difference.

It would be nice to prove it before spending any money though.

Yes, I think it is likely to be a stalk fault. Moving parts.

BCM is above accelerator pedal in RHD mk1 and mk2, assume it's similar on mk3, can give you pin numbers for indicator inputs tomorrow if useful.

Indicators have been done by integrated circuits within BCM-type units, instead of relays, since Mk1 Fabia. If you have a multimeter and an inclination to use it, you might be able to probe the relevant input pins at the BCM connector to see what it is being commanded to do. Does the car have adaptive cruise control? If so there's another module involved too, and possibly a clockspring.

Requirement for a sustained button press helps avoid accidental (bum-dialling style) boot opening. Unlike other doors, the boot can't re-lock itself automatically once it's popped, I think. Vaguely think the time can be varied with VCDS, 1 second hold, 2 seconds etc.

Yes, suffix HP seems to be more recent, alphabetically. Front Shock Absorber Škoda 1T0413031HP (skoda-parts.com) Suffix FN listed as equivalent.

The two systems have different 'resistors'. The Climatic (semi-automatic A/C) has this type of wound resistor (actually three in series with tapping off points and a thermal fuse) Climatronic (fully automatic) A/C system has a transistorised version that looks very different: I think @Wez5480 is saying is that he went looking for the former, but didn't find it because he actually has the latter (6Q2 907 521A for RHD; 6Q1 907 521A for LHD), which isn't in the same place. Both of those part numbers have been superseded by a suffix B version. Genuine ones are rather pricey.

Do you drive short distances mostly?

Odd thing is, I'm not sure that @Malume's car actually has ABS. Does it?

Dummy vehicle speed sender. It fills the hole on the gearbox and gives the redundant loom connector something to plug into. When these cars changed to using the ABS wheel speed sensors for vehicle speed calculation instead of a dedicated sensor in the position where you found that, they didn't bother changing the wiring loom. Instead they designed and fitted that piece of plastic and plug the wiring into it. It has no function except to fill the hole and give the wiring connector somewhere to attach.

Compression test on a diesel presumably involves removal of all glowplugs, which carries a risk in itself. Ask your garage what they would recommend, but maybe say that you think it could be the oil cooler (relatively much cheaper job compared to HG), see what they say. If you plan to do any diagnostics yourself, I think dropping the oil to look for coolant is a great suggestion. It will separate out and come out of the drainhole first, I think, if present.

Try scanning just the ABS module.