S13 Speed Sensor query.

Hi,
I have a 1991 Mitsuoka Le Seyde, which is totally based on a 180/200SX. It has a digital speedo and a head-up display - neither of which work or even illuminate, and nor does the mechanical trip or odometer. None of my cluster night-time illumination works either, although everything else works fine. I have removed the cluster, and all the usual parts (capacitors and resisters) that fail have been professionally renewed. However, it still does not work! So my questions are:
1) Supposing the gearbox speed sensor is working correctly, would that make the trip and odometer work even if the speedo did not work/illuminate? Or does the fact that trip, odo and speedo are not working point to the speed sensor as the culprit?
2) Would the digital speedo display a "0" if it was working (when the car was stationary) even if the speed sensor was faulty? Or does the speed sensor generate all signals including "0"?
3) Do you think the fact that both the night-time lights and speedo are faulty are linked, or do I have 2 distinct faults?
Thanks so much for any help. Andy

When my speed sensor went mileomeater stopped working if that helps

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the 200sx clocks are really different to the HUD 180sx clocks.

if you take the speed sensor out and put a multimeter on the terminals then spin the gear around then you should get a reading on the meters display.

if you do opt to buy a replacement check which one you have. the 200sx one had a metal body/red cog electrical connector on a long wire. the 180sx one could also be like this or be all plastic with the electrical connector on the sensor.

Thanks for the two bits of advice. I'll let you know how I get on, in case it helps anyone else.

It sounds very much like you've got the S13 silvia cluster and HUD (although some/few 180sx had them fitted)

The HUD will read 0 at all times until it senses a speed signal from the gearbox sensor.

All S13/S14 gearbox speed sensors are the same, its just the plastic cog on the end that is different, UK models have a red cog and I believe JDM have a white cog but I cant fully remember. The cog colours just indicate the amount of teeth for kmh or mph iirc.
The plastic body speed sensor Green mentioned is the S14a sensor (may also be fitted to the late S13 kouki but I cannot confirm, mine was auto)

I would remove the sensor and test the speed sensor signal at the cluster, it will pulse a negative or alternating positive/negative signal I cant remember which when the sensor cog is rotated. A multimeter should pick up a continuity signal but it may be hard to see so something like a noid light or power probe would be my weapon of choice (or get clever with a LED bulb).

The illumination circuits don't really cross, just on the earthing to the cluster but you'd know if you had an earth issue as the warning lights wouldnt work for starters. Illumination can only be a fuse, or the signal to the cluster.

hey norfy,, do you know how to get the s13 speedometer to work with an rb25 gearbox fitted.