Instrument cluster wierd fault

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XUD9TE
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Instrument cluster wierd fault

Post by XUD9TE » Sat Dec 16, 2017 5:10 pm

Hi, the instrument cluster in my car doesn't light up while the ignition is on. I can turn on my sidelights with the ignition off and everything lights up as normal and as soon as I turn on the ignition the instrument cluster lights turn off.



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james butler
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Re: Instrument cluster wierd fault

Post by james butler » Sat Dec 16, 2017 7:08 pm

sounds like a bad earth. try wiggling the wires that go into the bottom of the clocks just under the dashboard.


I dont mind project cars but I HATE SANDING!!!

XUD9TE
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Re: Instrument cluster wierd fault

Post by XUD9TE » Sat Dec 16, 2017 8:40 pm

I'll have a go at taking it out tomorrow and clean all the connections as I need to fix my odometer as well



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Re: Instrument cluster wierd fault

Post by mark1gls » Sat Dec 16, 2017 10:09 pm

If you are taking the cluster out go very careful with the blue plastic circuit board as it's very easy to damage it when removing the cluster.
Disconnect the car battery (earth lead 1st)

Good idea/time to "bulk out" the connection to the connection to the cluster.
Have read of this thread and links I've posted...

http://forum.sciroccoregister.co.uk/vie ... 11&t=21079


Mk1 78 Scirocco GLS 1.6 FR, weekend toy.
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mark1gls
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Re: Instrument cluster wierd fault

Post by mark1gls » Sat Dec 16, 2017 10:18 pm



Mk1 78 Scirocco GLS 1.6 FR, weekend toy.
Mk1 88 Golf GTi cabriolet 1.8 DX. Daily drive.
Membership No. 323

XUD9TE
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Re: Instrument cluster wierd fault

Post by XUD9TE » Sun Dec 17, 2017 12:46 am

Haha typical, now I see your replies and a guide after I've taken it all apart and fixed the odometer with nearly zero help

I was to impatient to wait till tomorrow so I took it out tonight using the light of my phone and a Philips screwdriver and stripped it down on the kitchen table. I found the metal cog at the end of the numbers was slipping on its spindle. I slid the pin out just enough to get the metal cog on the end out. I then put notches on the inside of it with a flat head screwdriver and when I put it back together the spindle felt tight going into the cog. I then turned the little red cog by hand and it was clocking up miles like it was new. It wasn't slipping anymore! Yay.

I'll go for a drive tomorrow morning and see if it clocks up the miles and see if I have put the speedo needle back in the correct place.

I then checked the plastic circuit board for any damage but there wasn't anything obvious wrong with it and all the connections seemed fine.

So I placed the cluster in place and plugged both connectors back and turned on my side lights... and nothing lit up at all! I then turned on the ignition and still nothing. Everything else seems to work like the oil and battery light etc.

Now I'm in a even deeper hole! Before hand the cluster would light up when the sidelights were turned on and they would go off as soon as you turned the ignition on

So now I need to find which wire in the connectors is the earth and which one powers the lights for the cluster and check them with a multimeter.

Does anyone know which wires does what on the two connectors?



XUD9TE
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Re: Instrument cluster wierd fault

Post by XUD9TE » Sun Dec 17, 2017 1:11 am

F**k I just read the guide to fixing the odometer and I effed up at the part where it says to lift the speedo needle off the stop and take note where it rests and then remove it. I didn't do that I just took it off as it was and when I put it back on I lined it up with the little white line that's below the stop pin. I just thought that was the indicator for zero I then lifted the needle slightly and placed it back on the stop. I hope it'll still be accurate.

Thanks for the guides though. I'll bulk up my connectors tomorrow and add that second earth to the main connector.

Hopefully that'll get everything sorted.



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james butler
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Re: Instrument cluster wierd fault

Post by james butler » Sun Dec 17, 2017 2:09 am

when you lift it over the stop it drops to about 10mm below the stop normally.
what you can do is pop the clocks back in the car loose and put the speedo cable back in.
take a drive with a sat nav and make a note of the speed difference between the speedo and the sat nav
then remove the clocks and pop the needle over the stop so it comes to rest on its own weight making a note of where it is now then pull it off and adjust it accordingly by how much out it was.
word to the wise make it read 2mph higher than the sat nav so your less likely to get caught by cameras as most navs are +-2mph out at 30mph ( when the speedo shows 30mph theoretically you will be doing 28mph)


I dont mind project cars but I HATE SANDING!!!

XUD9TE
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Re: Instrument cluster wierd fault

Post by XUD9TE » Sun Dec 17, 2017 2:52 pm

I've just been for a drive to the shop and back and by pure luck my speedo is spot on. I was doing 32 mph on the speedometer and the satnav was showing 30 mph. Also my odometer now works spot on.

Now to dig out my multimeter and sort out these electrical gremlins.



XUD9TE
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Re: Instrument cluster wierd fault

Post by XUD9TE » Sun Dec 17, 2017 7:03 pm

I've sorted all the problems I had with the cluster by adding a second earth point to the brown wire on the white plug. This fixed the coolant led constantly flashing and my rev counter not working with the headlights on.

I did still have a the problem of the instrument lights not illuminating the clocks. I found which wire was supposed to illuminate the clocks(white and blue on the white connector) I checked that with a multi meter and was only getting 10 volts for some reason. So what I did was take out the rear window de mister switch and splice into the blue and white wire that powered the light inside the switch and then joined it up to the blue and white wire on the connector for instrument cluster. And voila it works like a charm.



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james butler
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Re: Instrument cluster wierd fault

Post by james butler » Sun Dec 17, 2017 8:01 pm

great stuff
glad to hear you got it all sorted :good:


I dont mind project cars but I HATE SANDING!!!

XUD9TE
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Re: Instrument cluster wierd fault

Post by XUD9TE » Sun Dec 17, 2017 8:25 pm

Just another job ticked off the endless list haha.Now I just need to find the source of the water leak that's been soaking my carpet for the last month.



mark1gls
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Re: Instrument cluster wierd fault

Post by mark1gls » Sun Dec 17, 2017 8:27 pm

Good the hear its all sorted and a reply with what you have done incase others have the same problems.


Mk1 78 Scirocco GLS 1.6 FR, weekend toy.
Mk1 88 Golf GTi cabriolet 1.8 DX. Daily drive.
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mark1gls
Posts: 3061
Joined: Thu Apr 02, 2009 9:28 pm
fill in the right answer: 10
Location: Somerset

Re: Instrument cluster wierd fault

Post by mark1gls » Sun Dec 17, 2017 8:28 pm

Water leaks, door membrane split or missing, blocked drainage holes in the front scuttle (near the heater blower/windscreen wiper motor.
Do you have a sun roof?

Mybe best to start another thread


Mk1 78 Scirocco GLS 1.6 FR, weekend toy.
Mk1 88 Golf GTi cabriolet 1.8 DX. Daily drive.
Membership No. 323

XUD9TE
Posts: 17
Joined: Tue Aug 16, 2016 10:00 pm
fill in the right answer: 15

Re: Instrument cluster wierd fault

Post by XUD9TE » Sun Dec 17, 2017 8:36 pm

Yeah there's nothing worse than a thread that begins with a problem and ends with just "I fixed it thanks" it's always best to explain what you did to fix it as it might help others in the future.

I haven't got a sunroof, I'll check the drain holes on the scuttle tomorrow.

I'll probably start a new thread on the water leak.

Thanks for the info though! Much appreciated!