Our car broke down on 07/08/2021 and went into the shop on 07/12/2021. It was eventually determined the engine had to be replaced. The car was in the shop until 09/02/2021. The following day during a test drive I noticed some minor, unusual response, almost unnoticeable, from the brakes, but there were no warning lights or messages. I connected a code reader and received the following codes: U0422, U0151, and C0800. I think all of them are sent by the ECU and involve communication problems with the ABS and the restraint systems, but yet, no warnings. I took it back to the shop. They found a shorted or bad Body Control Module, probably caused during the engine swap. If I hadn’t found those codes, perhaps the brakes or restraint systems may not have performed correctly in an accident. Obviously, the BCM can be defective and no warning lights are displayed, yet the car seems to perform almost normal. My wife did not detect the unusual braking response. We have parked the car. It seems to me, if the BCM goes defective, there should be a red light, stop immediately warning. I think every system in the car has to communicate with it. Could it be a problem created in the factory?
NHTSA ODI 11436014