Xj8 gearbox fault

[Cdobbie]

Hi there. I have a 2000 xj8, I recently had a tracker fitted and a few days after it occurred a gearbox fault. I have put my code reader on and it is coming up gear 2 ratio incorrect. I recently put the car on Gumtree for spares or repair and somebody contacted me with this

"TO FIX YOUR JAG, DO THIS..

The ECU gets its information about wheel rotation from the rear abs sensor. This is matched up against engine rpm. If the information is wrong you would get a "Incorrect Gear Ratio".

There is always the question of whether the sensor itself needs cleaning as well.

In any case, the abs sensor data is the most likely cause of the message."

The car reverses no problem however once its in drive it will rev then bang into gear.

After getting that message it got me thinking about the tracker, maybe being connected to a wrong wire or accidentally cut a wire

Thanks in advance for any advice