Problem with gearbox going through gears speedometer not working .park neutral reverse drives are all selected at same time on dash. vehicle is 2.8 crd grand voyager 120,000 miles year 2004.I am a diesel mechanic with over 40 years in the trade this is my own vehicle never really had a lot of trouble with it until now,only other problem I've had is brake disc's and a rear ABS sensor all have been changed recently. I do have autol diagnosis equipment which covers most things on this vehicle I haven't used it yet. I was hoping it was going to be the speedo transsender, so I thought l would ask your advise first,david childs. Thanks.
Input speed sensor didn't cure problem .now going to change output speedsensor.