My RPM's stop reading is there a fuse or something that got disconnected ?
there is a sensor under the car... i unpluged it once and the speedo and rpm stopped working and i threw a p/n switch code...it was towards the passenger side of the car in the back
there is also a cord/wire thing that goes from the tranny to the cluster... that could be broken... and your cluster could be broken...
i dont know what car you have so there might be differences.... if i were you i would check the sensor i mentioned... then go to the auto store if that sensor is ok and get that cable i mentioned (just describe it and tell them your problem they will know what it is) and that thing is cheap... i had to buy it for an older car i used to have.... and if that doesnt work then go to a junk yard and replace the cluster....
thats everything i would do...
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