I want to check out my speedometer to check if all the wiring is alright. Do I need to remove the whole dash or can I reach from behind somehow? Is there a write-up anywhere?

 

Dang I forgot to check which car.

Oh well it is probably an A4 or an A6. You can pull the instrument cluster by getting about 4 screws on the underside of the black plastic chunk right below your speedometer (right above the steering wheel) it should span the whole length of the instrument cluster. THen pull another 2-3 screws that are behind the plastic that are holding in the clear plastic cluster. The whole set of instruments should come out, no dash removal.

 

The car is a 99 a4. The reason I want to take t out is to check if all the wiring is fine because every once in a while my tach drops to zero and the abs, brake light, and low oil pressure lights come on. I have another post where I asked that question. A friend said it was most likely the instrument cluster. How do I tell if something is bad? Whats a sign that something is messed up? And can you be a little more specific with your instructions? The're not too clear. Thanks

 

Do all the instruments drop (fuel, alt, etc?) it is probably a ground wire especially if the tach is dropping to zero but the car stays on.

I thought my directions were clear.

Ok, the speedometer is behind clear plastic.
put your finger at the center of the clear plastic.
Run your finger down the clear plastic to the first big hunk of non clear plastic you find.
On the underside of that piece of ~1.5 feet X 3" thick long non clear plastic is 4 screws.
Remove the four screws.
The long thin strip of plastic will come out but it has a tab on one end, so you pull out one end (the driver door side) then the other end.
Behind that piece of plastic is 2 or 3 screws which hold your instrument cluster in. After removing those screws it will slide out and you can look at all the wiring.

A ground wire should be loose or barely hanging on. Repair/ reinsert clip.

 

Sounds more like can data bus failure. Cehck for faults in the moules. You may want to try unplugging the abs control module and see if the other lights stay off. Then you know the abs control moudle is causing can data bus issues.

 

I took the instrument panel off but there was nothing wrong...everything was plugged in right. So it must be the abs control module. Where is it located? How do I get to it?

 

Wierd, every once in a w hile, my speedo jumps up and down from 0 to my current speed... sound like a ground wire ? No other gauges do it though, just the speedo.

 

Where exactly is the abc control module located? I checked under the rear seat but didn't see anything other than a black box that said alarm on it.

 

ABS ECU is built into the ABS unit under the hood/bonnet that's the block where all the break pipes go into,
also check vehicle speed sensor ( VSS ) for poor electrical connections this will also effect the speedometer

[IMG]local://upfiles/12092/795937FA46734ADF8E93948959926FEB.gif[/IMG]

 

So can I still unplug it somehow to see if it's the control module acting up? What exactly do I unplug?