Have a 2012 Mercedes sprinter 3500 van that the abs, traction control, and tire skid light is on. We have done the calibration for it, nothing happened. Replaced the brake light switch, still nothing. Replaced the abs control unit, still nothing. All sensors around tires are working properly. Also the battery was recently replaced with a compatible battery. Would like to know what else to try to get this thing up and running properly.