Test Point 5 - RPM signal
TEST POINT 5 - Rpm signal - Fault code 1_18Possible Causes, Elimination, Remarks
- Run test using an oscilloscope. Connect and adjust shop oscilloscope according to manufacturer's instructions.
- Connect oscilloscope test lead with terminal 49 and terminal 48 of the disconnected Digital Motor Electronics (DME) control unit plug.
- Start engine. Sinewave fluctuations of 3 V min. must now be displayed.
An intermittently higher amplitude indicates the reference mark signal.
1 - Rpm signal
2 - Reference mark signal
If the voltage signal is too low (< 3V), the gap between sensor and ring gear may be adjusted incorrectly.
Sensor gap: between ring gear and sensor: 0.8 ±O.2 mm (0.032 ±0.008 in).
- Using System Tester 9288, the reference mark signal may be read directly in the Input signals menu item.