Failed Clutch Position Sensor Issues. (2003 BMW Z4 3.0i)

Hello everyone,

I have been having issues with the clutch position sensor in my car. It started about two weeks ago, where the car was having some trouble starting in the morning. By the late afternoon, it would not start at all. By that, I mean that aux power would come on, but the engine would not even try to turn over, not even a click. After some research I thought that it might be the clutch sensor, as it controls the ignition lock.

I managed to start the car to get it home. Once there I put my theory to the test by shorting pins 3 and 4 on the connector to the switch (+12V and the full depressed sense line). The car started and ran normally. So I got a replacement sensor and installed it. That worked for a couple days and yesterday afternoon it failed, too.

In addition, I have done some testing on the switches themselves (they are solid state Hall effect sensors), though I am not sure how effective my testing was. I would use a multi-meter in continuity mode, and touch pins 3 and 4, note the value, then repeat with a magnet held up to the sensor. I got the same values and no continuity.

My question is, barring the fact that I may have received a faulty sensor (the new one), does anyone have an idea as to what the issue could be? My theories are that there may be some sort of voltage spike that kills the switch or that the wiring from the switch to the ECU may be degraded. Any help would be appreciated.

submitted by /u/Zarraya
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