There are fuses on the main circuit board to protect against cabling errors (and burning the house down etc..). One or more has probably blown. If you are proficient with an ohm-meter, you can check these yourself.
Otherwise, several of us here on the BBS know of them and could probe them (and replace blown ones) or help walk you through it. I can do it, but being in Canada (and you likely being elsewhere) makes shipping tricky.
Car support can fix it, but he's in The Netherlands, probably trickier than here, but guaranteed to resolve it. Others ?