Speed, lead from ABS
Speed, lead from ABS |
The ABS control module sends a speed signal to control module PSG 16 on pin K34. The signal is a square wave that varies between 0 V and B+ 29 times per wheel rotation. This speed signal is used to:
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determine the gear currently engaged. This ensures the engine receives the correct amount of fuel in different gear positions when the accelerator pedal is released.
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provide an impulse for cruise control.
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activate speed limitation by throttling down fuel quantity/combustion at 225 km/h
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Diagnosis |
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If the speed signal exceeds 220 km/h, is constantly high/low or is incorrect, DTC P0500 will be generated.
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System reaction to a fault
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Cruise control is deactivated.
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ACC is deactivated.
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The speedometer does not work.
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