Hi All, My son has a D1 200TDI which he has been fixing up, one of the final things before going in for a roadworthy is that is speedo is playing up. When you spin the cable from the transfer case end, the speedo moves. when you reconnect the cable and drive it works until you slow down then it stops working and doesn't start again. He has swapped out the gear at the transfer case end with a spare one, same results. Does anyone have any ideas on how to diagnose this issue?

Thanks

B