The front right brakes had worn down to bare metal on my son's 2012 Journey Crew. While installing new brake parts I could not push the pistons back into the caliper, so I purchased a rebuilt caliper. I completed the repair gave it a quick test and it seemed fine. My son drove the car the next day and the front right brakes were hot and smelled. I took the brakes apart and found it difficult to push the pistons back. A similar question on this site suggested it could be the master cylinder. However the ABS system is between the master and the caliper. So now I don't know if it is a faulty rebuilt caliper, the master cylinder, or the ABS system. How can I find the fault without buying a entire brake system.