Strage Electric Problem

[Simons]

Hi guys,

Today when I went to my car to go to my job I found some dash board lights on...like if the key was in first position...then I put the key in first position and the dash lights bright more powerfull and the engine starts without any problem. When I arrived to my job, I turn off the key but the engine didn't stop and the dash lights bright like in the morning, I cut the fuel to stop the engine, I disconnected the battery and the dash lights still bright...I connect the battery again an after 15/20' the dash lights disappear and all perfect...

I think that I have a problem with one underdash relay...anybody knows what will be damaged?? because I don't have the relay scheme to know the function of each one...I think that could be the upper left, it's the biggest one

Ignition on. 1st key position


Ignition off and the key out. Like I found it in the morning



After aprox. 20'...all good again


Any idea or the under dash relay scheme??

Thanks

[Rocco]

Sell that crap and buy a Dacia....

[Simons]

Do the same with your Ricers

[UrS4boy]

Failed ignition switch. Common.

[SteveH]

Yup, second the ignition switch

[UrS4boy]

Audi 80/90/RS2 Ignition Switch info

Failed ignition switch. Common.

http://12v.org/urs/IgnitionSwitchReplacementDIY.pdf

[macspring]

Third one for the ignition switch. Inexpensive to replace, not too hard, and worth doing when it is the original, given the age of our cars.

Lights on when the battery is disconnected is very very weird.

[macspring]

Do the same with your Ricers

Served Rocco.

[Simons]

+1 with the ignition switch...but the first what I did was unplug the connector...nothing changed...the dash bulbs light still alive

[Simons]

Served Rocco.

[Simons]

@ Urs4boy, Thanks for your detailed info, and all the other members opinions

[Simons]

I removed all the underdash and bonnet relays, discharge the capacitors...and nothing

Also the button retro light is on...

Any other ideas??

I think that I will take the schemes and the multimeter.....and some hours

[S2central.net]

Disconnect the battery - if the light stays on then you something special to share with us ;-)

Seriously though - if you had ALL the relays unplugged and still have lights on there is a short circuit somewhere - either the ignition switch or the light switch ... if its neither of those then you have some wires shorting together on the loom somewhere.

10 minutes with a multimeter should find the root cause. Thats optimistic for sure but it shouldn't be hours of testing - but it might be hours to find a damaged section of the loom. Would bet on a failed switch.

[Simons]

Disconnect the battery - if the light stays on then you something special to share with us ;-)

Seriously though - if you had ALL the relays unplugged and still have lights on there is a short circuit somewhere - either the ignition switch or the light switch ... if its neither of those then you have some wires shorting together on the loom somewhere.

10 minutes with a multimeter should find the root cause. Thats optimistic for sure but it shouldn't be hours of testing - but it might be hours to find a damaged section of the loom. Would bet on a failed switch.

if I disconnect the battery the lights and the engine turn off

I unplug one to each one, not all relays together...

This was the first think what I thought...the ignition switch, but I unplug the connector and nothing changed.

I took a look to this pdf and I was thinking on a fuse box problem...but if I have a wire or fuse box circuit problem, I will have it always, not after 20' all is good again...this was the main reason to think that one relay is bad

[mike74]

this link might be useful to you as well

http://www.pvv.ntnu.no/~shane/stasj/pics/motor/dokumentasjon/80/Electrical%20systems.pdf