Audi A4 1.9 tdi 2000 - Rev counter/temp gauge/fuel gauge all wrong !!

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Fri 7 Dec 2012 10:56
Audi A4 1.9 tdi 2000 - Rev counter/temp gauge/fuel gauge all wrong !! - k13 wjd

Hi guys, hoping to get some advice here.

Audi a4 1.9 tdi, 2000.

Rev counter isn't reading correctly ; reads 1000rpm when engine off, then if i cycle the ignition it reads 2000rpm engine off, cycle again - 3000rpm.....you get the idea. It then goes all the way back round to 1000rpm...


Temp guage reads 90 degrees out ( degrees TEMP) so stone cold its sat at 90 degrees, and as it heads up it goes up and hence warning overtemp comes on.

Fuel guage seems in-correct too, looks like 1/4 tank when it WAS 1/2 tank less than 20 miles ago.

Anyone have any idea what could be going on here ?? I have access to a decent diag unit, but have not plugged her in yet.

seen the problem before ???

Thanks in advance guys !

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Fri 7 Dec 2012 16:47
Audi A4 1.9 tdi 2000 - Rev counter/temp gauge/fuel gauge all wrong !! - tryitandsee

I'm constantly having problems with electronic readings on the dash (A4 B6 1.9tdi avant).

There must be a multi-link connector plug behind dash display and a loose connection somewhere that may be the problem. However I have cured most of my problems by putting in a heater/dehumidifier run from the mains electric. Also keeping the cars heater up high to dry out the condensation/damp behind dashboard.

Short journeys in mine never get the cabin temperature hot enought to keep things moisture free!

Edited by tryitandsee on 07/12/2012 at 16:47

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Fri 7 Dec 2012 16:51
Audi A4 1.9 tdi 2000 - Rev counter/temp gauge/fuel gauge all wrong !! - tryitandsee

.........and one other thing, in the fuse box drivers door side. I think you can take out the fuse to the dashboard display, which resets the module, worth a try.

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Sat 8 Dec 2012 10:43
Audi A4 1.9 tdi 2000 - Rev counter/temp gauge/fuel gauge all wrong !! - Big John

Fault suggestion No 1:-

On earlier Audi's if I remember correctly there used to be a three pronged voltage regulator plugged into the binacle circuit board that could either fail or more usually just work loose. This used to cause random gauge display issues.

Not sure if this is still relevant on a 2000 A4, worth a look though.

Fault suggestion No 2:-

Just in case - check the battery voltage with the engine running to ensure the charging system is not running over voltage. There is another (different to above) voltage regulator for the charging system that can fail.

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