Some owners of 2018 Cadillac XT5 vehicles may comment that the electric parking brake is inoperative. DTCs may be set in the EBCM: C028F (left park brake actuator circuit...short to ground) and/or C1586 (right park brake actuator circuit short to ground).
The Service Park Brake lamp may be on, with DTC C1587 (left park brake actuator software sensitivity) and/or C1588 (right park brake actuator software sensitivity).
This condition may be caused by water leaking into the rear actuator, creating a short to ground. If C1587 and/or C1588 is stored, this condition may be caused by software sensitivity caused by a weak battery. If DTC C028F 04 and/or C1586 04 are set, verify which EPB actuator set the DTC and replace the actuator. When replacing the brake actuator verify that it features the updated cover.
If DTCs are not set and/or the brake actuator have been previously replaced, or if C1587 0B or C1588 0B program the EBCM to the latest available calibration.