Hello Nuna
Your error is interested.It would be great if you have another same truck to try some parts.When you do acc on pedal pot look in screen and read is it voltage in operating values if not you need to move pot with hand and than to calibrate.Is it wiring of pot ok?
look battery on display sometime she know to be problem on still trucks just check it.And look CAN good because error that you have says that display dont receive data from traction converter.
If you can please replace pedal pot or every part that you think that dont work good,Calibrate all needed and check truck data are they ok for that vehicle.
Tell me what are you do.
Good Luck

Thanks Nemanja, I have checked the speed sensor - canbus and cleaned all the connection of the inverter. Now the truck can run without error code but only on creep speed.

I have used the Steds diagnostic to check the acc potentiometer voltage, i saw that when the drive inscrease the speed from 0-50% max speed the truck speed will follow - on the other hand if the driver increase more than 50% the speed will be dropped down to Zero again. I have done calibration the Acc. potentiomtera again but the problem is not solved yet.
Do you have any more experiences on this matter ?

Regards
Nuna

How I sow watchdog operate but no traction,if you check wiring and if can is ok check speed sensor and component of controller to avoid possibility of blocking controller, If everything is ok replace or open controller and check it.
Good luck with error.