Battery Safety Terminal (BST - COOPERS Only)
The BST is installed in the COOPER S due the battery location in the luggage compartment. The BST is used to minimize the possibility of a short circuit to the heavy gauge B+ wire that runs the length of the vehicle in the event of an accident.
The BST consists of a conventional clamp that is screwed onto the positive terminal from above and connected with a hollow cylinder. A propellant charge is stored in this hollow cylinder. Just as with the airbag and seat belt pre-tensioner, this pyrotechnic device is controlled and ignited by the MRS5 control module. The triggering strategy is also the same as for the triggering of the airbag, and it possesses identical protection logic. The overall unit is enclosed in a plastic shell that captures the cable if it is forced out and locks it so that a renewed contact is no longer possible.