The parking brake failure could have been water intrusion into the cab from a leaking sunroof drain or seal. I went to an independent and they pulled many codes from the brake module, including "major accident" which the car has never been involved in. They also dried out some of the electrics but that's as far as they could go without charging another $600 for a module, $500 to program or register it on the CAN bus all with no guarantee it won't fix it. So we're living without parking brakes. Have I said I'll never own another car with a sunroof? I've kept the drains clear but the seal around the glass leaked before I replaced it.

Erwin