On the back of the cluster you will find a big connector.
Open the connector, the brown wire is the ground and the white is the sensor wire.
- Remove the connector
- test resistance between jack 3 (ground) and jack 5 (sensor wire) 2K ± 200 ohm
- If you connect a mulitmeter (dc voltage) to those wires you should read a voltage when driving (30mls/h > 1 volt)
If the sensor works there is something wrong in the cluster.
Rob