Leon Instrument Cluster and Immobiliser

Col Max Pyat

Active Member
Dec 31, 2017
15
0
Hi all, sorry to be first posting with a query, but in fairness I've been lurking here a long time.

I've a Leon Mk1 that I picked up for my wife a few months ago, MY 2004, 1.4 petrol. Ran fine, but 2 problems. First was something I noticed first time I drove it at night: some of the warning lights on the dash are barely illuminating all the time. Traction control is one, forget the other. They're "ghosted on" but during ignition process they turn on properly, and then "go (almost) out" again. Wasn't running battery down, so I left it.

Second problem is that the immobiliser is now not working more often than it works. This led to a no-start in the morning one day, got car recovered to a local independent mechanic who did a bit of checking, and recharged battery (which flattened during all the attempts to restart car), and cleared codes. Car ran again, but he said he couldn't really claim to have done anything that would have resolved the problem.

It's recurred since, and at this stage my wife (who's 6mths pregnant) can't really drive it as she's so little confidence in it.

Now reading various threads, like this: forums/showthread.php?t=199145 I know that this can all be linked to bad connections at back of instrument cluster, and if I could get it out I'd be happy enough to have a go with soldering iron. However, I'm very unclear how to do that, as most of the threads don't have working pics any more. I paid the few quid for an hour's access to SEAT/VAG's Erwin setup, and couldn't really find a clear guidance either. Even having used the VIN to filter, I got apparently 2 versions of the instructions, one which was this:( can't post links, youtube vid id: RSSs1FrNE38 ) but doesn't work as I don't have the first 2 screws that are removed.
The second apparent version described stripping down the whole dash (steering wheel, airbags, etc.,) which I'm not going to do unless I'm very very sure I'm on right track.

So, if I can ask 2 questions:
Do folk think I'm on the right track with this? (i.e. instrument cluster repair as a possible fix for immobiliser woes)?
Does anyone have pointers on getting the instrument cluster out? (or where I'm I losing the plot?!)
 

Battoussai

Active Member
Mar 22, 2016
422
104
Portugal
Hi there.

I've done some removal of cluster myself and it's very easy the moment you done the first and second times. If you need any help I'll try to help more.

You can read this:
http://www.seatcupra.net/forums/showthread.php?t=430509

It's all down to this:

Removal of the instrument panel
There is no need to remove the steering wheel. However, the following illustrations do not show the steering wheel to facilitate the operations of compression.
– Pull the steering wheel with the height adjustment device, pull it right out and secure it in the lowest position.

– Release the upper cover -1- of the combined steering column switch. To do this, carefully pull it upwards.
E90-0062
– remove the lower -1- and upper -2- bolts that secure the dash panel shade frame.
– Remove the upper cover of the combined steering column switch.
– Remove the dash panel shade frame by carefully releasing the retaining clips -3-. Use tool -U-30800-.
Note
When removing the dash panel frame shade be careful not to damage the surface of the dash panel.
E90-0063
– Remove the upper and lower -arrows- dash panel securing bolts.
– Pull the dash panel towards the driver´s compartment and separate the connectors from the rear part of the dash panel.
– Remove the dash panel carefully so as not to damage its surface. To do this, protect the edges of the dash panel where the frame shade is located with masking tape and remove the panel carefully using tool -U-30800-.
 

Col Max Pyat

Active Member
Dec 31, 2017
15
0
Thank you very much for the reply!
Hi there.

I've done some removal of cluster myself and it's very easy the moment you done the first and second times. If you need any help I'll try to help more.

You can read this:


It's all down to this:

Removal of the instrument panel
There is no need to remove the steering wheel. However, the following illustrations do not show the steering wheel to facilitate the operations of compression.
– Pull the steering wheel with the height adjustment device, pull it right out and secure it in the lowest position.

– Release the upper cover -1- of the combined steering column switch. To do this, carefully pull it upwards.
E90-0062
I'm not sure if I understand what this is. "upper cover".
Is it the big plastic moulding that covers the piece of the steering column between the wheel and the dash? (i.e. with ignition on the bottom half of it). Or is the small "rubbery" panel that can be flipped up to reveal two screws? I'm nervous of just removing those two screws as very easy to drop them and they'll isappear down inside the dash if I do.
Also, I'd only expect to be able to see two screws (those two under the rubbery panel.

– remove the lower -1- and upper -2- bolts that secure the dash panel shade frame.
– Remove the upper cover of the combined steering column switch.
– Remove the dash panel shade frame by carefully releasing the retaining clips -3-. Use tool -U-30800-.
Note
When removing the dash panel frame shade be careful not to damage the surface of the dash panel.
E90-0063
– Remove the upper and lower -arrows- dash panel securing bolts.
– Pull the dash panel towards the driver´s compartment and separate the connectors from the rear part of the dash panel.
– Remove the dash panel carefully so as not to damage its surface. To do this, protect the edges of the dash panel where the frame shade is located with masking tape and remove the panel carefully using tool -U-30800-.
I'll try and post a couple of pictures later, but I think I'll have issues as I'm a new poster here.

car getting very damp and mouldy now as it's been laid up since just before Christmas. Think water ingress somewhere is also an issue :(
 

Col Max Pyat

Active Member
Dec 31, 2017
15
0
Mk1s common for door seals chap

In the winter my mates old mk1 1.4 would freeze on the inside lol

forged engine,revo intake,3" TBE r tech stage 2 -323bhp 333ftlb build thead:

Cheers, wherever the water comes in probably isn't so bad, it's only that when the car isn't being used and heated it builds up. Like how an old house gets damp when it's not inhabited, even though if you had heat/a fire on daily and were opening & closing windows and doors you'd never have a problem.

Had an old Mk 1 Saab 93 before, which was my daily drive, never had a problem. Then got another car and had the first one standing for a few weeks, and within a week there was condensation on the windows and a week or two more the mould started on the cloth upholstery, steering wheel, etc.,

Your build looks great. Feel a bit of a fool by comparison struggling to just get an instrument cluster out!
 

Leeoncupra

Active Member
Feb 12, 2017
764
191
Halesowen
Cheers, wherever the water comes in probably isn't so bad, it's only that when the car isn't being used and heated it builds up. Like how an old house gets damp when it's not inhabited, even though if you had heat/a fire on daily and were opening & closing windows and doors you'd never have a problem.

Had an old Mk 1 Saab 93 before, which was my daily drive, never had a problem. Then got another car and had the first one standing for a few weeks, and within a week there was condensation on the windows and a week or two more the mould started on the cloth upholstery, steering wheel, etc.,

Your build looks great. Feel a bit of a fool by comparison struggling to just get an instrument cluster out!
Wouldnt feel foolish.

Took me many years and alot of money to get to the knowledge i have and yet theres a million things i still am yet to learn.

Searching on here and google helps alot and is free teaching as you inturn learn from others mistakes/problems

Count yourself lucky lol

forged engine,revo intake,3" TBE r tech stage 2 -323bhp 333ftlb build thead: http://www.seatcupra.net/forums/showthread.php?t=440348
 

Battoussai

Active Member
Mar 22, 2016
422
104
Portugal
Thank you very much for the reply!

I'm not sure if I understand what this is. "upper cover".
Is it the big plastic moulding that covers the piece of the steering column between the wheel and the dash? (i.e. with ignition on the bottom half of it). Or is the small "rubbery" panel that can be flipped up to reveal two screws? I'm nervous of just removing those two screws as very easy to drop them and they'll isappear down inside the dash if I do.
Also, I'd only expect to be able to see two screws (those two under the rubbery panel.


I'll try and post a couple of pictures later, but I think I'll have issues as I'm a new poster here.

car getting very damp and mouldy now as it's been laid up since just before Christmas. Think water ingress somewhere is also an issue :(

You are going great.
I really don´t take the upper cover (yes, its the cover of the steering column).
I just take the small rubbery panel and undo the two screws. Yes, they can fall into the dash and will be a pain to recover. Before you unscrew them just fill the hole below them with a rag or cotton or something that prevents them to go down to the dark.
 

Col Max Pyat

Active Member
Dec 31, 2017
15
0
OK, some progress but not a solution yet.
Popped out those two screws, successfully retrieved them without loss (relief!), handily enough got to back of the cluster unit and after a bit of fiddling got the hang of the release mechanisms on the connectors (blue and green).

I then stripped down the unit and went over all the solder joints on the green connector (melted each joint and added a tiny bit of extra flux-cored solder, afterwards checked for any inadvertent short-circuits, and all seemed good). I put the unit back together and fitted to car. Not fully fixed.
The engine started (which is a good sign but doesn't guarantee anything as immobiliser worked sometimes anyway). However the "ghost lights" persisted, which tells me I've not fixed things (yet). Also, even though I thought I'd put needles back right etc., the dials are all a bit haywire now.

I was looking through the PDFs I'd saved from Erwin, and it seems that the Blue connector has the "basic functions" which includes speedo, fuel, tacho, ABS, coolant temperature, etc., so the fact that the ghost-lights haven't been quenched may not be so surprising as I haven't touched this connector yet with soldering iron. Meanwhile the green connector is the one that includes immobiliser (relay output, coil reader), so that could well be fixed already.

Anyway, even if immobiliser turns out to be sorted, I still need to rectify gauges. I've disconnected battery again, removed cluster, and have it on workbench. What I'll try at weekend is
  • strip down the cluster again, including...
  • remove the needles without twisting
  • resolder pins on the blue connector,
  • look over green connector again.
  • reassemble cluster, put needles all back on at zero
  • reinstall cluster in car
  • cross my fingers, reconnect battery, see what happens!

Should I try anything else?
Should this get the needles back in sync? (i.e. so mileage/temp/fuel/rpm are more or less accurate?).
Thanks again for the help and encouragement so far.

(Edit: on needles, could another option be to leave the front-glass and needles off the cluster, connect it to car, turn ignition to "on" but not start engine, which should zero all gauges, then slide needles on in "zero" positions, finally reattach the glass front?)
 
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Battoussai

Active Member
Mar 22, 2016
422
104
Portugal
Hi there.

Glad you've managed to strip all down.
The question of the needles is very simple. When you take the needles off you have to twist them right? Right. Thats how I do it too.
However when I did reinsert the needles on the dials all fancy on the zero position I saw that when I start the car all of them were off sync. It seems the gauges re-align to the correct position when you start the engine.
My solution was to start the car without the needles on. Then GENTLY and without TWISTING insert the needles on the dials: RPM is inserted on the mark of 900RPM as its the Diesel idle timing. SPEED set at exact Zero and then see if at exact 20km/h it locks the doors (I have that security measure enabled). The TEMP gauge just let the car warm up and insert the needle on 90ºC as its my normal temp. For FUEL just drive it until it hits the reserve light and beep warning and set the needle to the second mark on the dial (mine beeps at the second mark).

Regards.
 

Col Max Pyat

Active Member
Dec 31, 2017
15
0
Well I've had the instrument cluster in and out of the car a few times now, getting pretty handy at it, and at stripping it down :lol:

However, not sure I'm on right track. I retouched the solder joints on the blue connector, put it back in car this afternoon, but I still have some faint warning light illumination even with power off (traction, the temperature LED, something else). Also, the immobiliser isn't actually fixed, sometimes it fails to disable, sometimes it works fine. The cluster illumination is also intermittent. Gauges do seem to turn on (they were originally intermittent too).

I took the cluster out again this afternoon, and brought it back to workbench. I desoldered all the pins for each connector, and then resoldered them cleanly as I could. I haven't reassembled/tested yet.

Is there anything else I should be soldering/testing? So far, I've only been working on the soldering of the two connectors. Also, I guess this could be down to the wiring harness or something else more difficult to trace. The connectors themselves look clean & dry, so I haven't tried cleaning those pins etc., nor have I been cleaning the fuses or their holders.

Once I hit 15 posts I'll post a couple of pictures.
 
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Col Max Pyat

Active Member
Dec 31, 2017
15
0
Just to update:
Reassembled and reinstalled the cluster into the car this morning. I really thought at first that I'd fixed things as I couldn't see the ghost-LED illumination that was usually there... seemed like happy days, but...
Was going to clean up the car this afternoon, but when I went to sit in, I could see that the illumination remains, it was just too bright earlier to see it. I tried multiple goes at turning ignition and also managed to recreate an immobiliser fault too. :cry:

In any case, I cleaned up the car, but I'm at a bit of a loss. I'm rather confident now that the solder joints between the connectors (blue and green) are solid. I've reworked them multiple times, and essentially fully remade them. Apart from needle-offsets, I've never made it any better or worse, so far as I can see.

However, the fault pattern does seem to indicate something related to the instrument cluster as a whole, since I've a collection of observations in that direction:
  • coolant level alarm
  • coolant level light flashing
  • intermittent illumination
  • intermittent failure of needles of gauges to respond
  • ghost illumination of warning LEDs
  • intermittent failure of immobiliser to function correctly
Is there anything else it could be that would give this family of faults? (ECU on way out I guess could do it?) Is this something that can be cost-effectively brought to a garage? Car's worth €700 tops, and that's with everything working. If it stays like this, I'll try to get the NCT (MOT equivalent) renewed and then sell it for €100-200 to someone who needs short-term wheels and is able to live with the uncertainty of immobiliser (which my wife cannot).
 
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endoftheworld

Active Member
Aug 31, 2014
22
0
Wales
I have a similar fault that occured last year, it began with the dashboard illumination flickering then coming on permanently even with the key out and the car locked. A few weeks later the ABS light stayed on but no fault was logged and both ABS and traction control still work well.

I got it through the MOT by pulling the LED from the cluster but it needs fixing properly.

My instrument pack was dry and had no signs of damage.

I couldn't find any online reverse engineering or specs on ECUs, location, pinouts etc, no service manuals to be found either, but apparently it could be a wet or faulty Convenience Control Unit (body controller) which I haven't had time to look for yet but may be somewhere beneath the steering wheel.

I also think it might just be a diode breaking down in the instrument pack but haven't had time to check that yet, whatever it is seems to be fairly common in old vags so if I solve it I'll follow up here with the cause and the fix. I intend to look at it this weekend.
 

Col Max Pyat

Active Member
Dec 31, 2017
15
0
I have a similar fault that occured last year, it began with the dashboard illumination flickering then coming on permanently even with the key out and the car locked. A few weeks later the ABS light stayed on but no fault was logged and both ABS and traction control still work well.

I got it through the MOT by pulling the LED from the cluster but it needs fixing properly.

My instrument pack was dry and had no signs of damage.

I couldn't find any online reverse engineering or specs on ECUs, location, pinouts etc, no service manuals to be found either, but apparently it could be a wet or faulty Convenience Control Unit (body controller) which I haven't had time to look for yet but may be somewhere beneath the steering wheel.

I also think it might just be a diode breaking down in the instrument pack but haven't had time to check that yet, whatever it is seems to be fairly common in old vags so if I solve it I'll follow up here with the cause and the fix. I intend to look at it this weekend.

Cheers!
As it stands, I think I'd still get it through an NCT (Irish MOT equivalent), assuming the immobiliser doesn't strand it on the ramp or anything! But it's not a feasible vehicle for reliable use.

Your symptoms are different to mine, so if it's a diode breaking down (for example) we've probably got different diodes breaking down. Also, since both of us have a progressive failure (i.e. it's not a single symptom-cluster that's coming and going, but a range of symptoms coming/going at different times in different combinations), that also points to it not being a single diode/capacitor/wire/whatever that's working/not-working.

Like yourself my instrument cluster itself is dry and shows no signs of moisture.

Have you started a thread for your own issue?
 

endoftheworld

Active Member
Aug 31, 2014
22
0
Wales
I haven't started a thread yet I wanted to learn a bit more first, waiting for it to stop raining here in Wales but that may never happen so I'll just get wet. Yes it is different in detail but it wouldn't surprise me if your fault and mine are both caused by the same module in a stupid location getting wet.

VW seem to have made a point of distributing the modules all over the place, in doors, both sides of the dash, footwells, everywhere. But at least the VAG system is easy to plug in and work with and the parts are cheap and plentiful. Hopefully will have a look on saturday.
 
Jun 16, 2021
2
0
endoftheworld did you ever get your instrument cluster fixed?
I am experiencing identical fault on seat Leon MK1 2003.
Would much appreciate any troubleshooting or fixing tips.
 

mty12345

Active Member
Jun 17, 2011
3,727
451
bristol
endoftheworld did you ever get your instrument cluster fixed?
I am experiencing identical fault on seat Leon MK1 2003.
Would much appreciate any troubleshooting or fixing tips.
I had the same fault and ended up sourcing a brand new, old stock cluster for £150 (SEAT wanted over £400) That then gave me the chance to troubleshoot the old one, without the worry of bricking it, and although I didn't test it at any great length, it definitely seemed to have sorted the problem when I took it out for a short test drive.

Basically I reflowed the 2 green and blue connectors that are circled in the attached pic. DON'T attempt it unless you're fairly experienced at soldering and feel capable of doing it without damaging the board or bridging the pins though!!
Use a suitable iron (I was worried about melting the plastic connectors if using hot air) and plenty of good quality flux and it's a fairly easy job. If you don't think you're able to do that safely then there are companies that you can send them off to to be repaired.
Hope that's some help.

insturment cluster.png
 
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