[Andy_E_32]

If someone can help me with this I will be very grateful. At the moment I am driving with a torch in order to see my speedometre!

The problem is as follows. I have an Audi 80 Avant 1.9 TDI, 1995 model, estate. There is no dashboard illumination or illumination of the heater panel bulbs. However, the interior lights (luggage, vanity light, courtesy light, hazard light switch, rear heater switch, fog light switch) all work fine. In addition, the lights to show my indicator direction, oil pressure light, handbrake light, airbage light etc all function correctly. I have checked all fuses in the engine bay and they are all working. I have tested the rail voltage on the heater panel bulb mounts and this is giving a positive reading of 12 volts so I am certain it is a wiring problem and not an earth fault.

Have I ignored a relay or a fuse tucked away somewhere other than the main fuse box? All suggestions greatly received.

Kind regards,

Andy.

 

[labonga]

Hi there!
I have the same problem with my avant 80 1993, but tought it was the ligt bulbs that was dead? isnt it? could it be the dimming switch?

 

[Audi 80 ABT NZ]

Originally posted by Andy_E_32@Oct 24 2004, 04:57 AM
If someone can help me with this I will be very grateful. At the moment I am driving with a torch in order to see my speedometre!

The problem is as follows. I have an Audi 80 Avant 1.9 TDI, 1995 model, estate. There is no dashboard illumination or illumination of the heater panel bulbs. However, the interior lights (luggage, vanity light, courtesy light, hazard light switch, rear heater switch, fog light switch) all work fine. In addition, the lights to show my indicator direction, oil pressure light, handbrake light, airbage light etc all function correctly. I have checked all fuses in the engine bay and they are all working. I have tested the rail voltage on the heater panel bulb mounts and this is giving a positive reading of 12 volts so I am certain it is a wiring problem and not an earth fault.

Have I ignored a relay or a fuse tucked away somewhere other than the main fuse box? All suggestions greatly received.

Kind regards,

Andy.

Quoted post​

Hi, just a thought, can I assume you have checked your tail lamps still work? the one fuse usually caters for all the things you have trouble with.

 

[bhb399mm]

sounds like you have a problem with the acutal bulbs. I can't be sure, i havent seen an 80 pannel in ages... my guess is there are several bubls lighting your gauges and they have just burned out. Try pulling the pannel off and seeing what it looks like behind everything. If you cant find anything best bet is to take it to a garage.

 

[audi80eesti]

Hi,

I just logged on to post my own similair problem. Initially I noticed that my rear fog light was staying on, I had a look at the problem and could find nothing wrong. Then that problem cleared all by itself (or so I thought), the only problem is that now my dash lights are only on when I turn the rear fog light on. ????

Anyone else had the same problem ??

 

[kris6445]

Cheing the fuse man I have the simolar problem i chengd it and is ok naw so do i brat mi!

 

[imessiah]

I had exactly the same problem. I checked the bulb and that was fine, i checked the fuse and that was fine, and yet the indicator and the clock lights etc were all working fine. But when i got it checked, it turned out the dimmer had gone, so the dimmer was by-passed. Maybe that's the problem, dunno.

 

[stshort]

:banana:

Hiya, I too am same problem with my 1991 2.0 sport and I think I know what the problem is. assuming the 1995 electrics are not too different from mine.

Living in sunny (not) england, water ingress seems to be the problem. From what I can gather the instrument cluster lighting has no relay feed and is fed from a 5A fuse that sits in the fuse compartment in the bulkhead of the car. I found that the seal had gone in the bulkhead causing water to corrode and short contacts in the bulkead fuse box, kinda silly putting an electric junction box containing fuses in a rainwater gully on the car. The underneath of the fuse box including cables can be seen by removing the interior panels on the bottom of the dash. Previously I have loosened the fuse box out of position and applied silicon sealant around the edge of the box, which worked fine for a couple of months. I now have the same problem again but the 5A fuse is permanently blowing as if connections are shorted so am about to sort again. I was also going to have a look at the switches on the steering column first just to check for bad connection as taking out the fusebox is a right pain.

Hope this helps,

Steve

 

[A6_25TDI]

Originally posted by stshort@Sep 1 2005, 12:17 AM
kinda silly putting an electric junction box containing fuses in a rainwater gully on the car.

Yes, it's very silly indeed. Guess what, on my A6, they moved the fusebox inside the car, but they placed the Engine ECU exactly where the fusebox used to be on the Audi 80. Now that's very clever :angry:

Hope you get it sorted out...

 

[stshort]

Done some further investigation in to "check lights"

All exterior lights come on on car despite no interior illumination.

Have pulled apart the dimmer switch and found that the variable resistor inside the switch is ok and working varying the resistance between 1Kohm and 1.4Kohm.

The lamp inside the dimmer switch is blown.

I dont think replacing dimmer switch would solve the problem though, another fault is still present on the lighting circuit which is blowing fuses and possibly blew this lamp in the first place. I am sure that Audi in their wisdom would not place this lamp in series with the rest of the lamps in the dash so that when one blows they all go off. I have replaced blown lamps behind the speedo previously that still allowed all the other dash lights to still light.

I have a circuit diagram of the dimmer switch now which I will post on forum when I get chance which may be useful for other people fault finding

Steve

 

[pgphamm]

I have exactly the same problem! Just recently bought an Audi 80 1.6 from '91 and indeed, none of the dashboard lights are working. All the indicatorlights are fine but none of the illuminationlights work. Any progress? I'll try to find the dimmer today but I couldn't find anything wrong with the fuses, they seem just fine...
Keep us posted!

 

[kilo]

Originally posted by audi80eesti@Nov 13 2004, 01:38 PM
Hi,

I just logged on to post my own similair problem. Initially I noticed that my rear fog light was staying on, I had a look at the problem and could find nothing wrong. Then that problem cleared all by itself (or so I thought), the only problem is that now my dash lights are only on when I turn the rear fog light on. ????

Anyone else had the same problem ??

Quoted post​

Hi,
When I had that problem,ie the rear fog coming on and the switch not turning it off I checked all the lights and if memory serves correctly the numberplate light and panel lights were off.

The problem turned out to be the feeds to the bootlid in the rain gutter had fractured internally where they bend after the hinge clips. Can I suggest you unclip the cable with the lights on and bend it around a bit,mine looked perfect externally but by bending it slightly lights started working and I could feel a definite weak spot.
I cut thru the insulation either side of this point and V carefully slit it and peeled it off,it revealed 3 or 4 of the wires had broken and were possibly shorting internally this gave a similar effect to a dodgy earth.

This must have been happening for years because when I first bought the car at 3 years old it flattened the battery and the techie said "I think the bootlight is staying on,I'll remove the bulb" this was not satisfactory so I replaced the bulb and checked the action of the boot light.As the light went off about 3" before latching I assumed (wrongly) the presence of a mercury switch,with the wires now bodged up the light doesn't go off till it latches and all the gremlins have dissapeared.

May not be the same in your case but it seems to be an acknowleged design fault that will only get worse with age due to the plastics hardening. If anyone finds a tidy,permanent,fix could they share it with us as I intend to keep this car for as long as possible.

Ian

see also :http://www.audi-forums.com/t4212-rear-wiring.htm

Sorry, thought this was a Hyperlink,but you get the gist?

 

[byrnsey]

hi all. just found this site when looking forsame answer to problem. My dimmer switch was turning the dahboard lights off so I had to keep fiddling with the dimmer for months until eventually it just stopped working. Garage said it burned out the dash circuit board. Makes sense that that would be the same for all the problems here, as other lights and fuses are working.

Could Steve with the circuit diagram please post it. thanks

Adrian

 

[RichardB]

Hi,

New to this forum. Comments seem very helpful.

I have a 94 Audi 80 and too have the same problem. Instrument cluster lights just gone. No fuse problem. Auto electrician has loked and cannot find problem. Can only think it is linked to dimmer switch and possibly burning out as an earlier reply has suggested on this forum.

The other issue I have is all the gauges die on me i.e. the fuse blows for now apparent reason. Again cannot sauce the problem. Can only think it is related to location of fuse box, possible ingress of water etc,etc...


Any thoughts out there???


Thanks

 

[byrnsey]

Hi Richard

It looks like we are the only recent members to the forum with this problem. I had a mechanic look for the problem four times - yes 4. And quickly lost all faith in his abilities. My dimmer switch was replaced but he then realised there was no currrent to the switch (so I paid for a new switch for no reason).
Eventually he "figured" as it is not on a fuse it was actually on the same circuit as the the licence plate lights - which were indeed gone. Another member has mentioned that in this forum.

Basically I have still not had it fixed as I am trying to find a mechanic who actually can fix it. The first mechanic I told him the problem but he took all those attempts to try and find the problem!!!! My adivce is to print these messages and bring them to your mechanic as a guide...

let me know if you come up with anything concrete.
As for the actual guages not working I'm assuming that they must be on a fuse so that's another problem for you.

Adrian

 

[RichardB]

Adrian,


Thanks. I will keep you informed of developments!!


ATB


Richard

 

[RichardB]

Adrian,


How much did it cost to have the dimmer switch replaced? I can think this is the only reason why the dash lights are not working.

Thanks


Richard

 

[byrnsey]

If only it was that simple. Even the mechanic thought once he replaced it the lights would work. the switch was only about £25. But I had it replaced and the dash lights still don't work. It was after that the mechanic had two more investigations to find the problem. THat's when he figured it is something to do with the wiring to the licence plate lights.

I have actually just spent the last hour fiddling with all the wires in the boot and checking fuses etc. I did find a two wires disconnected to what must only be an earth - at the actual boot lock. Connected it but no difference.
I also just popped over to another mechanic who gave me a number of an electrics specialist to call which I will do shortly.

Next time you're at your car just check if your licence lights are working as a matter of interest.

Adrian

 

[RichardB]

Adrian



Licence plate lights working. I am convinced that it is the dimmer switch, as until you had mentioned it I had not even considered this option.

I will have a look at the fuse box housing this weekend as someone quite rightly commented on the early/mid audi's the fuse box is located externally right in line on the water soak away, so there is the possibility of terminal corrosion.

Will keep you in touch of developments!!!


Cheers


Richard

 

[byrnsey]

hi richard

I've booked my car into "another" electrical specialist on Monday so I'll update next week. Hopefully with an illuminated dashboard.

Adrian