Speed signal

The input of the driving speed signal (V-signal) is required in the DME control unit for several functions.

• It serves the purpose of maintaining the programmed maximum speed.Once this speed is reached, the individual ignition and injection signals are masked out.This ensures smooth shut-down.
  
• On vehicles with the air conditioning switched on compressor activation is interrupted up to a driving speed of 13 km/h when accelerating under full load.
  
• The idle speed is controlled at a driving speed signal > 0 km/h, i.e. the idle speed has a fixed value which is normally just above the engine speed when the vehicle is stationary.
  
• The idle speed is controlled if the driving speed is 0 km/h. However, it is still corrected by the air conditioning system signal, the drive stage information on automatic vehicles and the light switch input.
  
• The incoming V-signal in the DME control unit is made available via the CAN interface to the adaptive transmission control unit (AGS).