brake warning light fault found,but not cured A6 2.5 TDI 96.

Camped on the site Joined: Feb 20, 2009 Posts: 272

hi chaps,i recently posted about my red brake warning light flashing.thanks for your many replies.ive had the fault traced to the cluster.does any body know of a company who can repair it,or does anyone,have a spare cluster,its a 1996 2.5 tdi a6. thanks steve

Posted: Wed Mar 03, 2010 10:03 pm

Is it there all the time or just when starting then goes away? if its the red warning with bleeps this is level warning not pads and is often a ghost warning see this thread about ghost warnings..

http://www.audifans.net/ftopict-30105.html

does your car have a/c btw?

Camped on the site Joined: Feb 20, 2009 Posts: 272

it beeps,then the light flashes all the time ,yes it does have a/c.had it checked out at auto electrics,and he traced it back to the cluster.have not tried the chassis earth strap yet.its a bit of a mystery cheers steve

Posted: Thu Mar 04, 2010 11:39 pm

I had a long standing issue on my A4, rear brake warning light would come on intermitently, rear wiper wouldnt work properly and one rear number plate light would always fuse. Transpires that number plate light wire was corroded, replaced this and no more problems with rear wiper or brake light warning indicator Cool

Posted: Fri Mar 05, 2010 12:37 am

Does you car have have fuel computer btw?

I have a few instruments you could test with to rule out, easier if you are passing Chesterfield (M1 J29)...

Note replacing the cluster will loose you your milage to whatever the new cluster has and you should only source TDI instruments due to rev counter red line difference and mpg calcs in fuel comp version

Camped on the site Joined: Feb 20, 2009 Posts: 272

no,it doesnt have the fuel computer,just the okay check,which,doesnt display because of this fault,as i said before its been tested,and it points to the cluster,could it just be a dry joint?,the guy at the auto electrics,who i know well,said he could send it away to be done,but said the firms who do this sort of thing,charge silly money,and tries to avoid sending things to them.i thinking of just leaving it to flash away,but it would drive me mad,and i hate having niggly faults.one point,why if you start the car with the door open it doesnt flash,but when you close it it does?

Posted: Fri Mar 05, 2010 10:40 am

It's odd I I'm not understanding it myself fully, but i've not had much to do with non fuel comp instruments (which are different)...

I think i have one set of instruments like yours so if you are willing to pay the postage costs, I can send you them for a test, if they work with or without curing the fault at least you'll know if it really is the cluster..

The saloon i have also has non fuel comp so while using my instrumemts you could send me yours and I can test your cluster in my car as well, shouldn't be expensive either parcel post or parcel to go etc..

let me know

Camped on the site Joined: Feb 20, 2009 Posts: 272

great idea,it least ill know one way or another,ill give you my details on a pm thanks steve,did you get my last pm

Posted: Fri Mar 05, 2010 3:26 pm

yup I think so? about headlight? i replied later as I missed that..

Will get the instruments packaged over weekend and send on monday, have to swap them into the saloon just to see they work ok first

Posted: Mon Mar 08, 2010 6:09 pm

Ok getting instruments ready I have re-read your post and I'm confused by something, I only ever come across two types of instruments on A6 TDI that's with or without fuel comp

The set I have without fuel comp (that I was going to send you) has 4 warning symbols with separate bulbs instead of the auto check system, but as said re-reading you are saying the auto check isn't showing because of the brake warning..

All instruments I have with auto check also have fuel comp, hence not sure what you have and want to send you something you can use

Two things to confirm this a good picture, or better still the instrument code (part number) from 17 with Vag com, or on a sticker bar code usually on the top of the instruments on the white plastic between where the rev counter & speedo sit.. you should only need to pull the instruments out slightly to read this..

The two types I have are:-

4A2 919 035 DR fuel comp & auto check

4A2 919 035 DQ non fuel comp & auto check

Camped on the site Joined: Feb 20, 2009 Posts: 272

hi mate just got in from work,so cant take out tonight,but yes it does have the four seperate warning bulbs cheers steve

Posted: Mon Mar 08, 2010 10:46 pm

Ok I'll send you a 4A2 919 035 DQ non fuel comp & auto check tomorrow.. it's tested working fine in my saloon TDI no brake light warning..

It's reading 188K miles all bulbs working

Camped on the site Joined: Feb 20, 2009 Posts: 272

great stuff,thanks very much cheers steve

Posted: Wed Apr 07, 2010 9:15 am

Ok an update with a conclusion..

The cause of the problem was indeed the Cluster. It's seems corrosion on the pcb in the cluster was casing the warning check system to short. There was minor corrosion on some of the PCB traces a few of the bulb connections, and the pin array of an IC.

I cleaned all these with electrical contact cleaner, checked the PCB both sides with a magnifying glass to be sure, and it solved the problem. In testing the warning system still operates as normal so no damage done and appears to be working fine a few weeks on