a computer program that hooks up to a odb2 reader. lets you scan all the modules etc. look in the modifications threads there is one labeled alpha odb. Jscan may also see the fault I did not try it but it does see other modules faults.
dealers have not earned very much trust the past few years and they should of been able to see the fault and chase the circuit pretty easy. The wheel heating circuit and module are pretty’s simple systems to check. the module also controls your seats so if the seats work the module gets power fine. if the module is shutting off because of error there’s a code. So that leaves wire harness, clock spring, or wheel itself. otherwise it is probably just a bad module which is by far the easiest part to replace.