how much does it cost to have an OBD repaired.

You may have a bad engine computer, however check your fuses in your fuse box to make sure they are all good. Your OBD2 socket may be tied in with your 12v power supply in the fuse box area so I would check your fuses first and retry the code reader. If all fuses are good I would assume your engine computer is faulty and needs replacement. Auto parts stores can order you a new computer pre-programed for your vehicle provided you bring in your old one for the part numbers and matching codes on the computer body. Cost can run a few hundred dollars for the computer and if you have a chipped key you will have to have the new computer reprogrammed for the key at the dealer or a qualified locksmith can do it also.