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Reluctor sensor - No rpm during cranking

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Hi everybody,

My first (and maybe stupid) question on this forum:

I have a engine strapped on the engine dyno from which i struggle to get a starting rpm.

The concerning setup has a custom trigger (60-1 / reluctive) and is controlled by a Link xtreme ecu (program attached).

Already did a triggerscope as attached.

Ecu settings:

type: Reluctor

Filter: Level 1 (low)

Tooth count: 60

missing tooth: 1

Would be great if anybody can point me in the right direction!

Attached Files

Do you get a trigger waveform using the oscilloscope function that Link has?

Yes, the trigger waveform is present ((attachment: Trigger_1.jpg) But the runtime values don't display any rpm during cranking. Which led to my suspicion that the falling/rising edge was not recognized so i added an extra missing tooth (60-2) but still no sign of progress..

The most likely problem is that your arming level is too high at cranking rpm. The voltage from the sensor needs to exceed the arming threshold before the ECU will recognise a valid signal. You can confirm the amplitude of the signal at cranking speed with the ref sync capture. As a general rule you want the arming threshold set at about 1/3 of the peak amplitude. Based on your attached pic you'd want the arming threshold to be around 0.3 volts. You've also got the polarity of the ref sensor around the wrong way as evidenced by the shape at the missing teeth. What is the air gap between the sensor and trigger whee;?

Thanks for jumping in so soon Andre..

-I've already tried setting the arming treshold at it's minimum value (0.2) combined with reversed polarity.. But still no rpm signal

-The air gap between sensor/trigger wheel is 0.9mm.

Normally i wouldn't mind switching over to Hall effect but in this case the entire wiring loom is already tucked & twisted in raychem :(. So my hope and guess is that this setup will eventually work since it's my first experience with a link ecu.

Problem solved, incorrect settings for trigger 2.

Thanks for thinking along!