Breezy_Pete

Where's the humidity level sensed? Don't think I've ever seen reference to a humidity sensor in these systems?

Yes. Tayna.co.uk are very swift at delivery usually. May as well try charging though, nothing to lose. Be persistent though; may take a few goes.

3 One-touch electric window function will need resetting. Do you know how old the battery is?

The two window regulator units have a direct data (LIN) connection between themselves, as well as connections back to the central convenience unit (J393). Not sure how that is relevant, if at all; but it might be why the two units seem to 'swap faults'? The logic of the door open switches is such that disconnecting the lock from the window regulator will be the same as the door being closed from its viewpoint. The door-open microswitches short to ground when the door is open, and break the circuit when door is closed.

The circuits say that the (non-ground) connection from the door open switch goes to both the window regulator unit and the onboard supply control unit. If it's possible try viewing the doors' status (open/closed) in measuring blocks of both J519 (module 09) and J393 (module 46, I think). See if they disagree when the window reg unit is unplugged. I wonder if the fault with the passenger door lock remains, and is actually the ground connection to the lock unit, as I found on one last summer on our mk1, rather than the microswitch itself. The microswitch wires go into the board at the bottom of the photo and the left hand (ground) one can be seen going to the dodgy joint of the connector. 20200910_155143.mp4

Compare compression with other cylinders.

Relay is the same thing as the control unit. It's all solid state now, no moving parts.

Do you weld?

Check fuse 15 under the bonnet. Your engine code would be a helpful piece of information in getting to the right wiring info.

When you say you've changed the battery, do you mean DIY, or you had it done by a garage/dealership?

Consider investing a little in the VW tool set that allows removal and refitting of the subframe-plus-consoles without losing the alignment of the consoles relative to the chassis: VAG Subframe Locating Pin Set 4 Pc Subframe Alignment Tool Golf Audi Polo 6189 | eBay I think that's the right tool, but double check before buying. The point is that the two relevant holes on each console that the M12 bolts go through to hold it in place on the chassis have 17mm clearance holes. This is how the front alignment is set up in the factory, by the waggle room within those oversize holes. I haven't done the job but I think the idea is that you remove the M12 bolts - one at a time - and replace with one of these, which when tightened up gives a 'dowel' effectively for the refitting of the consoles. When refitting you slide the consoles up onto these dowels, and remove one at a time to replace with the bolt. The fatter parts of the tool can slide relative to the thread axis, which is how they fix the original positions when tightened up.

LED, so unlikely. May have been nobbled though... Voltage-related faults can be just battery disconnection, if you've done that at any stage?

I think 434 is the answer, but if you take apart your current key/fob, you should find the info printed on it somewhere, e.g.

This was a passenger side module on our mk1. Tkae lots of photos as you go along if you do decide on dismantling for a look; will probably help reassembly.

A little example of such a broken joint. I think it's a mechanical wear and tear thing with years of door shutting and consequent flapping of the loom near the connector. This one wasn't easy to spot initially because of the conformal coating painted over the solder joints: 20200910_155143.mp4

Skoda Catalog [europa] (7zap.com) That's what I'd use. Don't try it on a phone. they tend to reduce the number of columns of info, often dropping important ones.

Have you definitely checked the right one? Sometimes Skoda fail to differentiate clearly between LHD and RHD fuse layouts, leading to confusion. The correct one is 25 Amp rated.

Have a look at the 'basic equipment' section of the circuits, particularly the ignition switch. Terminal 75 is one of the outputs of the switch at pin 2, going to the load reduction relay (J59) coil, the onboard supply control unit (J519), and anything commoned to point A33 in the circuits. It seems to only be powered direct from the ignition switch at the first position of clockwise rotation. It's not obvious to me just now what's going on with this. J519 can presumably maintain/control this A33 rail independently of the ignition switch. The connection of this to the engine ECU looks a bit like a 'wake up and get ready' signal? Looking forward to understanding this better!

What problem are you addressing?

The OPs' car in this thread is a turbodiesel, so the likely impact of EGR delete on real world emissions would be significantly more NOx, marginally less CO2 and probably lower particulates. What's your stance on NOx and its impact on human health in the immediate term? Interesting and somewhat forceful first post. What vehicle(s) does your family drive?

Top mount bearing may have been killed by a broken spring. The top coil can break which then doesn't sit right against the bearing. Oh, and don't worry about warning lights that show before engine is running. (Except battery light which you definitely do want to see at ignition on).

I think you're correct about lock part numbers. I don't think the window motor unit will have any relevance. I don't think the lock wiring even connects to it? Will check later when I get on a big screen. Edit: One or two wires from the lock do go there, but in my experience the problems are usually at the lock unit itself (on mk1s), and/or on mk2s the door bellows are a dodgy design so always the first place to look.

Same here. Only time ours played up, a new battery made it all work perfectly.

I presume you're measuring that between battery negative post and the clamp, disconnected from it? You need to let the car shut down completely first, and then do the measurement without waking it up again. Any interruption of the connection will wake things up, so you have to be a bit stealthy. Try this: Open the bonnet Loosen but don't remove the battery negative clamp, make sure you can wiggle it free/off with minimal effort Flick the bonnet latch over so that the car thinks the bonnet is shut, even though it isn't, giving you access to measure current use directly at battery negative. Lock the car, all doors. Making sure the key is outside the car. Wait 30 minutes. With multimeter on 200mA DC Current range (or similar) and probes in the appropriate meter sockets, put the negative/black meter probe onto the battery's negative post, straight downward. Hold the positive/red meter probe against the battery clamp in such a way that you can keep it on there (and the other one still on the battery post) while you gently jiggle the negative clamp up off the post around your black meter probe so that you now have everything connected through the meter (and the power to the car was never interrupted). This operation is probably much easier with an assistant, but quite doable solo. Read the true quiescent current now. Slip the negative battery clamp back down/on, remove meter probes, tighten clamp. Open up car and operate the bonnet release to reset the catch.

Crucially important, I would think. Have you looked into what is involved in making a secondhand cluster work in a different car? My vague feeling is that it's not particularly straightforward.