Hi Edgardo

I dont have information for that specific truck but most of the time the fault codes are kept similar to that of other models by the same manufacturer.

27 and 28 relates to either the motor field circuit or the controller side which drives the field transistors or circuitry.

30 is related to pump circuit and is most likely triggered as a result of the original traction code which prevents the line contactor from energising.

Has the truck been out in the rain at all? Sometimes it may be earth faults to the truck motor or controller side which can throw up various faults.