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Front Passenger's Seat Belt Contact (USA_LHD) (Help Texts)




Belt Buckle Switch With Voltage Interface

The oscillographs shown here only apply to belt buckle switches with 4-pin connectors. These switches have a 4-wire Hall sensor with voltage interface.

The 4-pin adapter lead 61 6 032 must be used for the measurement. The adapter lead must be attached to the connector on the seat belt buckle and the wiring harness. The multifunction cable MFK1 is connected to the adapter pin 1 (terminal 31) and adapter pin 3 (cable to MRS control module). The oscilloscope is set by the test module.

Set curve
Fig. 1: Seat belt not inserted in belt buckle


Waveform:






1: Signal form: Square-wave
2: Low level approx. 0.8 V

Set curve
Fig. 2: Seat belt inserted in belt buckle


Waveform:






1: Signal form: Square-wave
2: Low level 0 V

Set curve
Fig. 3: Break


Waveform:






Belt buckle disconnected or line break
1: Signal form: Saw-tooth