Speedo not working over 20mph

**Aeikostx** · 21-03-2009,11:10 PM

Right, I should start off by saying that I'm not technically minded so you'll have to bare with me if I don't understand any replys. I was driving home as normal when I noticed my speedo dropped right down to 0. I quickly slowed down (as the reason I checked the speedo was because a speed camera was ahead) and the speedo started working again and jumped at 20mph. I then accelerated as usual, and it dropped back down to 0 after I had gone over 20mph. When I changed into 2nd gear, the speedo literally bounced between 20-30mph and then went straight back to zero.

After an hours driving, it was unchanged and now the car is parked on the drive. I can't afford to take it to the garage just yet, so I'm wondering if this is a common problem and what I need to do to fix it. I heard B5s have electronic speedos, so no speedo cable to worry about then.

EDIT: I've taken it out this morning, and the problem now has gotten really bad that it doesn't register speeds under 20mph anymore. The fuel reading also bounces from Empty to Full randomly - which also affects the DigiDisplay. Also, the mileometer no longer increases and the same mileage from yesterday is on there, even though I've driven 40-50 miles today. Please Help!!

**Aeikostx** · 22-03-2009,05:12 PM

Someone please help

**Alan02** · 23-03-2009,02:18 PM

Hi, sounds like an instrument cluster fault.As you mention the fuel gauge fluctuating also.You can only check the wiring plugs on the back for good clean contact.Maybe remove,check and replace,also check earth connections to it.Then try.The mileometer wont register as the speedo is faulty.

**Aeikostx** · 23-03-2009,05:15 PM

Hey Alan, thanks for the response. It now seems to work as I took it out for a drive and the speedo registered to 40mph (didn't get a chance to go on any higher speed roads) but it developed the same fault near the end of the journey. This time however, the speedo started to dance between 30-35mph while I was in that speed range, and the corrected back to 40mph when I got to that speed.

Is a new instrument cluster an expensive fix?

**Alan02** · 24-03-2009,02:25 PM

Hello again. I`m doubtfull as to wether you can get it repaired,if indeed it is found to be an internal fault.As mentioned,maybe check the wiring first and take it from there.There may be
some place that can test and repair them,but they may be hard to track down?

**Aeikostx** · 03-04-2009,11:46 AM

*******UPDATE**********

Well it's been diagnosed and it turns out I have a slow water leak at the back of the engine. The water is dripping onto some electrical wires which have corroded and are giving false signals. They're going to replace two hoses, the wires and the sensor (coupled with the diagnostic fee and labour) this has totalled up to £156. Not sure if that's reasonable or not, but at least I'll get my speedo working again! Thanks for the replies Alan

**bohoo** · 06-04-2009,11:00 PM

youd be better buying a sat nav as audi speedo is approx 4 to 5% out and it would be cheeper

**Alan02** · 07-04-2009,06:23 PM

Originally Posted by Aeikostx

*******UPDATE**********

Well it's been diagnosed and it turns out I have a slow water leak at the back of the engine. The water is dripping onto some electrical wires which have corroded and are giving false signals. They're going to replace two hoses, the wires and the sensor (coupled with the diagnostic fee and labour) this has totalled up to £156. Not sure if that's reasonable or not, but at least I'll get my speedo working again! Thanks for the replies Alan

Hi there! Pleased to see you got to the bottom of it.

**Aeikostx** · 09-04-2009,10:38 AM

Originally Posted by bohoo

youd be better buying a sat nav as audi speedo is approx 4 to 5% out and it would be cheeper

Thanks for the reply. I already have a satnav, but it was the fuel gauge not working that really had me worried. For the work that I do, I drive 140 miles a day, and relied heavily on my electronic fuel gauge to work out how many miles I had left in the tank. Now it fluctuates up to 100 miles above and below what I really have in the tank and I worry I'm running on fumes.

**sharpy1.8t** · 09-04-2009,10:01 PM

hello did you get this sorted?
i have the same problem but my speedo has stopped altogether.
i sent it to bba-reman this week to get repaired but they phoned me today and said it was unrepairable.