VN Calais L3 Speedo likes to GO SPASTIC... HELP???????

[DJDONII]

Can anybody tell me why my speedo has just staring to jump around all over the place most of the time it will register what speed im doing and then it will just die completely but if i floor it sometimes it'll come back on but then go off again or just go spastic im totally stumped

any help would be greatly appreciated,

Josh

[88GreenVN]

Probably the speed sensor in the gearbox or the voltage regulator in the cluster.

[Shearer]

Also check fuse for the 'Instruments' (fuse 10 I think?) My speedo was behaving in a similar manner and I found fuse was blown.