I seem to have a faulty speed sensor (again). Historically it would work, then fail a minute or two later on would come the red HICAS light. The garage appeared to have fixed it - all was well.

 

Then this moring it beeped once or maybe twice, and then went round to 320+KM and jammed the needle against the stop. Then a minute or so later along comes the old red HICAS light. Stoping and starting seeems to re-set it but then it fails straightaway.

 

The auto box works fine, the other gauges appear to be doing more or less what they are told.

 

So my question - am I correct in assuming that the speed sensor has failed again? Two failures in quick succession (we're talking use measured in hours) - is this indicative of something else?

 

It's off to a local specialist (not the supplying dealer) on Wednesday to have the cam belts done and cure a weeping oil seal, I think I will get them to look the whole car over as I fear it may be duff. Or is this just normal 300ZX gremlins?

Speed sensors dont go that often. You are unlucky to have one go on you in the first place.

 

Was it a new one which you put on? Sounds like the speed sensor was faulty. Can you not change it?

Sounds to me like you need to verify that the wiring to the speed sensor is good. Get it checked out with a multimeter.

Check one of the wires havent come loose, mine did not long after having a new one fitted, they are quite close to the zorst and can get cooked quite easily.

 

Attached is well used, ever useful speed sensor pic!!