I was having issues on my NX with the tach not working. Here is the link to thread on that. TN8man had a good post with the frequency that the pick up sensor would be reading at different RPMs.
First time posting here on TBN. I致e been having issues with my NX5010. The Tach had kind of been on and off the past year or so. No it just won稚 work. It seems to try and do the sweep at start up but only moves 1/8 or so. I tested both ground connections on the é„* dash plug. Everything...
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You should be able to hook up a multi meter with a frequency setting or even better yet an oscilloscope and read out the frequency. Your engine may have have a different scale but if its a bad sensor I would think you could see the frequency jump around at the same rpm range as your tach does.