ME engine speed signal - function - GF07.61-P-3017SM

ENGINE 113.986 

ENGINE 113.987 

ENGINE 113.988 

ENGINE 113.989 

Signal assignment 

Fig 1: Signal Assignment Of ME Engine Speed - Engine 113.986/987/988/989

The short circuit-proof engine speed signal TNA is generated in the ME control unit (N3/10) from the signals supplied by the crankshaft position sensor (L5) and forwarded to other control units via the CAN databus.

When the crankshaft is rotating, an alternating voltage is generated in the crankshaft position sensor by the teeth of the driven plate. During this operation, each tooth generates an alternating voltage signal. No voltage is generated as a result of the gap created by 2 missing teeth. The engine control unit detects the TDC position of cylinders 1 and 6 from the 2nd negative slope after the gap.

The engine speed signal TNA is a square-wave signal with a constant on/off ratio of 6 pulses per engine revolution and a maximum current of approx. 20 mA.

If no signal is received from the crankshaft position sensor, the signal from the camshaft Hall sensor (B6/1) is used as a substitute (emergency mode).