ok so i sent in my 300zx to get a "check up"/wheel allignment etc. and dispite my instruments being "tempramental"... ie randomly stopping and starting whenever it pleases.. the diagnostic equiptment that they used picked up no faults.. was just wondering if this would pick up faulty sensors that the instruments rely on or would the cluster be at fault meaning a new cluster is needed. cheers, dylan.
Possibly a dud speedo unit, but I doubt it because of the intermittent nature of the fault. The first place I would look is the speed sender unit at the back of the gearbox (go to the tech section and you will see exactly where to find it). Make sure that is plugged in and the wires not damaged. If that looks OK, maybe a forum member has a spare to lend you to check it out. This sort of fault is way outside what would be covered by a "check up" (whatever that means) but if you had mentioned it to your mechanic, he could have had a bit of a look while it was up in the air.
I had some issues like this. Sometimes the speedo would work fine then it would read random like 30% of the actual speed or zero or 220km/h. Most of the time it was fine. I went to an instrument specialist they couldn't find the fault and said I either needed to replace the cluster or the circuit board on the cluster. I had them install a new circuit board and it was all fixed.
My speedo was working then playing up , also showing 300 kmh on and off and all over the place was also beeping over speed witch it never had done.It was a dry soldered joint on the rear of the speedo on the r10 marked resistor ?.Maybe check that.
i had this problem, ended up being dry joints on the speedo circuit board. refer to original thread for some hopefully useful info: http://www.aus300zx.com/forum/showthread.php?p=356312#poststop good luck.
