Crankshaft Position Sensor: Description and Operation

GF07.04-P-6010KE Component Description For The Crankshaft Position Sensor
- ENGINE 271.921 /944 /946 /948 up to Model Year 8
- ENGINE 271.940 in MODEL 203 up to Model Year 8
- ENGINE 271.940 in MODEL 209
- ENGINE 271.941 /955 /956

Arrangement







L5 Crankshaft position sensor

The crankshaft position sensor is located at the left rear on the crankcase.

Task
The crankshaft position sensor detects the crankshaft position and motor speed.

Function







L5 Crankshaft position sensor
C Gap (2 teeth missing)
D Teeth (magnetically conductive)

The distance between the crankshaft position sensor and teeth on the drive plate or flywheel (ca. 0.8 mm) is not adjustable, but is determined instead by the installation position.







L5 Crankshaft position sensor
a Tooth leading edge
b Tooth trailing edge
c Gap (2 teeth missing)
h Signal from crankshaft position sensor
l Screened signal line
s Coil (inductive)
V Signal voltage in volts

The leading edge of a tooth generates a positive voltage pulse and the trailing edge a negative voltage pulse.
The distance from the positive to the negative voltage peak corresponds to the length of a tooth.
he gap produced by 2 missing teeth results in no voltage being generated in the crankshaft position sensor. This gap is used for detecting the TDC position of cylinder 1.