High-voltage connector
12 Volt connector
The vehicle has five safety circuits.
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Safety circuit 1 passes through battery regulation control unit J840, maintenance connector TW and switching unit for high-
voltage battery SX6
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Safety circuit 2 is located within switching unit for high-voltage battery SX6
Safety circuit 3 is in charging unit for high-voltage battery AX4
Safety circuit 4 passes through voltage converter A48 and electrical air conditioner compressor
Safety circuit 5 is located within high-voltage heater (linear) Z189
The safety circuits in the vehicle are ring circuits that pass through the high-voltage components and control units/contact bridges
in the connectors.
They are supplied with a 10 mA current from the 12 Volt electrical system.
If a safety circuit is interrupted, e.g. if a connector is unplugged, data bus diagnostic interface J533 receives a notification from the
relevant control unit. A signal is sent via the dash panel insert CAN directing control unit in dash panel insert J285 to show a mes-
sage to the driver. It is possible to continue driving until the ignition is switched off. It is not possible to reactivate the drive sys-
tem.
Maintenance connector TW
Maintenance connector TW, also referred to as the high-voltage interlock or service disconnect, is located in the centre front of the
vehicle. It is both an electrical connection in the 12 Volt control circuit for the high-voltage battery power contactors and a compo-
nent part of the safety circuit. Unplugging the maintenance connector TW opens the safety circuit and breaks the 12 Volt control
circuit of the power contactors. This provides a redundant safety configuration. The maintenance connector serves to de-energise
the high-voltage system.
Please use the relevant program in the vehicle diagnostic tester to properly open and de-energise the high-voltage system. After
being opened, maintenance connector TW is secured from being switched back on by the padlock T40262/1.
The maintenance connector is also the primary emergency cut-out connection.
684_053
An information label is affixed to maintenance connector TW.
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