I'm not sure exactly...both told me they weren't getting any codes from the transmiss. computer, and they had about 8 pages of a "problem tree" to go through to figure out what was wrong. Since the car by then had been in repair shops for two whole days w/o a diagnosis and w/o anyone being able to retrieve DTCs, I'm not sure they really know what to do, and it may be their scanners simply won't pick up something that the dealer's scanner would.