Speedometer crazy

[aussie320]

Please Help. My speedometer is acting up. When I start driving the guage races up to around 95kph and stays there, even if vehicle is going faster than 95kph. It is only when the vehicle speed decreases to around 10kph that the needle returns. Same thing happens in reverse.
Vehicle is a 91 320i E36.
The voltage at the sender unit is approx 5V, the sender unit has conductivity.
This problem occurred after I received the car back from panel beaters. Could they have shorted a wire for the system? Is the guage faulty (hope not, I would need a second mortgage to get new one), sender unit or is there another black box in the system that could produce the fault?
I need to resolve this urgently, I dont want to get any speeding fines.

regards
PJ

 

[aussie320]

Problem solved

Hi Everyone,
I resolved the problem. I noticed that one coil of the guage was not working, therefore problem lay in the cluster.
I removed the cluster (two screws in dash, unplugged three connectors, rotate and squeeze through the top of the steering wheel) and separated the electronics from the guages (three torx screws and undo two levers either side). All guages tested fine electrically. I noticed that one of the long contacts on the speedometer meter had excess solder resin and the insulator cup was distorted. Removed the resin and trimmed the insulator. Put back together and Bob's your uncle.
Hope this may help someone in the future.
regards
aussie320