I took all apart on rear brake system and thouroughly went through it all...I found nothing. I took it to the dealer and they are not able to find anything or duplicate the issue. It happened all the way to the dealership...no rear brake that is...pedal depressed all the way and no action. They just shook there heads as they couldnt get it to happen and said they worked fine. Any thoughts...it is my strong feeling it is the rear master cylinder.
Assuming the caliper has been checked over and found serviceable, I would replace the master cylinder at this point to be assured of brakes. It very could be a cup problem in the MC itself.
As it is more than likely that the seals in the master cylinder are faulty then a rebuild kit for the master cylinder should do it
The main part in the rebuild kit will be a new piston with the seals already fitted