Breezy_Pete

Only other thing to mention is the bits (kindly shown by the above) in between the motors. These microswitches and resistor combo will be to give positional feedback to the door control unit, to tell it when to stop driving the motors (i.e. limit switches). These won't be involved with control unit unconnected, so I would 'dab' at the motor connections with the 12V, rather than apply continuously. You'll probably hear a change of running speed at physical end of travel range. It might be informative to measure (resistance) between the two pins that connect these switches to the door control module before doing any powering of motors. This ought to tell you if either of those microswitch are currently closed/conducting, by reading 0 ohms or a finite resistance. Pins 6 (brown/black wire) to 7 (brown/yellow wire) at 20-way connector. Or both may be open as shown, so meter will read overlimit. Exactly what you do with the information gleaned, I'm not sure, but data is always good to have when available.

Do you mean at the lock module, or the door control module? I was thinking you could unplug that 20-way at the door control module and feed 12 and 0V into the pin numbers mentioned above, by poking thin wires into the appropriate contacts of the loom connector? Could actually just link across from the contacts that the thick brown 0V and thick red/yellow 12V appear on. Make any sense?

There was probably contact sparking/arcing that put interference on all 12V supplies for a time.

Well done. Interesting how it caused other problems! Your electric windows are not really affected by any other modules. Driver's side and passenger side motors are data connected to each other, but nothing else. Unlike the earlier pre-facelift version which are CAN connected. Message me for more help.

The first thing probably worth checking is the 12V permanent power to the thick red/yellow, and also the thinner red/violet feed going to the 20-way door module connector. If you measure relative to the thick brown earth wire on pin 20 of that connector, you'll be testing the earth continuity through the bellows too. There does seem to be two motors within the lock module, a lock motor and a safelock motor. Not really sure what the normal sequence of operation is, but they share one common wire, the green/yellow at the lock connection. The lock motor has a blue wire also going to it, the safelock motor has a grey/yellow. I assume that when locking and unlocking there is a 12V potential difference applied on these wires. So for one direction of lock movement the common, green/yellow would be at - say - 0V and the other two wires given 12V, probably one after the other? For the other direction, the common would be at 12V, the other two earthed. You can access the non-lock end of these wires at the 20-way connector that goes onto the door control module. Pin 11 is the common, green/yellow, 12 is the grey/yellow, 13 the blue. You could just play around with applying voltage to these wires and hoping to unlock it.

Replace it when the car struggles to start on a few consecutive days.

1K0413031BF is exactly the same part whatever brand you might find it in.

I will try to look at wiring info at some point this evening, not sure if there will be one or two motors within your lock module, but there ought to be a way of sticking 12V across a pair of now accessible wires to unlock the door.

Pure water will have the highest heat capacity, so will boil slowest for a given heat input.

I would keep the tyres for another year if there's plenty of tread, imagine if you put a new pair on and got an unrepairable puncture in one soon after. Where's the oil leak origin, did they say? Can be due to the oil separator on the back of the engine being clogged, causing excess pressure in the crankcase.

How much tread left on the tyres? Does that quote cover every item on that list? I would ignore some of them, like the exhaust corrosion, and possibly the brake hose ferrule corrosion, probably even the console bushes if you haven't noticed any handling problems or graunchy noises with the car.

I'm away this week anyway, but it sounds like a relay change by post might be feasible with a bit of planning. Code read/write usually done via the diagnostic port, but unnecessary if relay is changed on original unit. Not too sure how to eliminate all other possibilities, but intermittent work/not work wouldn't surprise me with burnt contacts.

It was unlikely you would be neighbours, but worth asking.

Yes, there are threads with photos and descriptions of process. Most mk2 Fabias and Roomsters currently on the road will have at least one broken, or repaired door loom wire, I expect.

Are you anywhere close to this place? https://www.1769.fi/ I know the guy that runs it. He would solve this very rapidly if you need help.

No VW or Skoda dealerships?

From where did you buy the replacement brake light switch? Genuine are not heartbreakingly expensive.

There's a plug/socket pair at the A-pillar, the wires that break are part of the door loom side of that connection, within the rubber boot. Access is awkward for in-situ repair, but do-able with patience and a modicum of dexterity and soldering and heatshrinking. (Door) Loom replacement is the official fix, but there are a multitude of kits on ebay etc that consist instead of just the female connector, plenty of pre-crimped contact inserts with short wires to fit into it, and you just cut and shut these into the existing door loom beyond the point where they flex in the door hinge area. Solutions for all.

@PhiloB whereabouts are you based? There's a way of testing the motor by just shorting two of the contacts of one of the plugs that goes onto the control unit, immitating the relay being energised. Possibly not going to be easy with a bad back though. Coding a replacement control unit (on a pre-March 2010 built car) is very easy, just one 5-digit code to read out of existing and drop into new one once installed. Registered copies of VCDS Lite can do it, as well as full VCDS. Another control unit might have a relay with contacts that are also worn out though. Can't remember if I have one at the moment and can't check this week.

There is one unused connector I can think of. It goes to the gearbox, top of diff area next to offside driveshaft flange. Before ABS modules used wheel speed sensors to calculate road speed, there used to be a speed sensor there. Now the loom connector just plugs into a plastic dummy sensor. Not much help in your quest, sadly. It may have even been designed out by 2009, not sure. Have a look.

No, unfortunately you'll barely find a spare centimetre of wire in the bits supplying items that are fitted, let alone any spare connectors for things that aren't.

Quite possibly the relay inside the BCM. There's a guide to replacement in the Fabia Guides section. Soldering involved. Yours will be the BCM with part number suffix F, the second relay type mentioned in the guide.

Yes, single XZN (not Torx). M8 size from memory.

Dead ends will be broken wires, unless you just mean apparently unused positions in the connector? It's surprisingly easy to remove the door entirely. Unplug connector, one XZN screw for the check-strap, two 13mm nuts one in each hinge. Would make access for repair massively better. Nearly did that myself last weekend on a Roomster, but there was only two busted wires, so I carried on in that horrible cramped space.

Yep, with mk2 Fabia and Roomster, always the most likely problem.