CLK 320 Cabriolet (208.465) V6-3.2L (112.940) (2000)
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Logic section
After the ignition is switched on, system initialization and safety checking is started. The system is enabled following a satisfactory check sequence.
The conditioned input signals are processed in the logic section and the following values are calculated
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Vehicle speed from the front wheel speed signals.
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Vehicle acceleration from several successive wheel speed measurements.
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The control unit checks the voltage signal from the diaphragm travel sensor every 3 ms. The pedal speed is calculated from the voltage difference
between two successive measurements.
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Learning algorithm: calculation of vehicle deceleration for adaptation of triggering threshold to different braking system conditions.
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Threshold: this is calculated from the basic threshold (vehicle identification values), vehicle speed, brake pedal speed and the values from the
learning algorithm.
If the calculated values exceed the specified threshold, BAS activation is initiated.
BAS activation is interrupted immediately following a signal from the BAS release switch.
Safety circuit
The task of the safety circuit is to detect faulty signals in the control unit and faults in the electrical cabling system.
The following components are monitored continuously:
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BAS solenoid valve (A7/7y1)
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BAS diaphragm travel sensor (A7/7b1)
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BAS release switch (A7/7s1) and
^
stop lamp switch (S9/1).
If a fault is detected, the system switches off. This is indicated to the driver by switching on the indicator lamp:
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BAS, BAS/ETS, BAS/ASR or BAS/ESP indicator lamp (A1 e39, e49, e48 or e47).
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In models 203, 209, 215, 220 via the multifunction display (A1p13).
In addition, a fault code is stored in the control unit.
The safety circuit also constantly monitors the battery voltage. If the voltage falls below 10 V or exceeds 16-18 V, the system is also switched off until
the voltage returns to the specified range.
GF42.31-P-4500A BAS Control Unit, Location/Task/Function
GF42.31-P-4500A BAS control unit, location/task/function
