In the event of a crash of sufficient severity, the battery terminal isolation is triggered. The interruption of the positive lead (charge wires) prevents a short circuit or high currents.
The safety battery terminal (SBK) consists of a cone and a counterpiece with a priming cap. The priming cap enables electrically controlled separation of the cone and counterpiece. The battery safety terminal (SBK) is installed in the positive lead just in front of the positive terminal of the battery.
The control modules right B-pillar satellite (SBSR) and auxiliary module 1 monitor the vehicle battery and the starter battery. The control module right B-pillar satellite (SBSR) registers the criteria for activating the battery terminal isolation. The control module right B-pillar satellite (SBSR) also provides the current impulses for ignition of the priming caps. The information transfer to the SBSR is across the Safety Information Module (SIM). The information for the auxiliary module 1 is transferred across the K-CAN SYSTEM data bus.
In the event of a crash of sufficient severity, the priming caps are ignited by defined current impulses. The accumulating pressure presses the cones with the positive leads out of the counterpiece far enough to interrupt the positive leads.
The control module right B-pillar satellite (SBSR) provides the ignition impulse for the safety battery terminal (SBK) in the positive lead to the vehicle battery. The control module right B-pillar satellite (SBSR) also provides the signal for ignition of the safety battery terminal (SBK) of the starter battery to auxiliary module 1.
The control module auxiliary module 1 provides the ignition impulse for the safety battery terminal (SBK) in the positive lead to the starter battery.
The vehicle electrical system cable is not interrupted in this operation. Electrical consumers, e.g. starting motor and fuel pump, are switched off.
The starting motor load circuit is interrupted. The engine can no longer be started.
Note:
The interruption of the starter line is displayed as a Check Control message in the instrument cluster. An intermittent gong also sounds.
Fault memory entry
The batteries must be disconnected for prior to any work on the power supply.