Vehicle speed sensor.

[Bowers155]

Hey guys! Having a little trouble with vehicle speed sensor.
Voltage to sensor only 8.3v when should be 12v even when checked at dash panel (brown and red wire). Disconnecting wiring harness from black bulkhead connector still no different. Also tried a spare dash panel I had laying around exactly the same so it’s defiantly a wiring issue some place maybe a feed or earth possible from the dash panel effecting or pulling to output to that sensor down? Also fuel gauge seems to fluctuate when driving quite a lot “when harsh braking or acceleration”.
Thanks in advance

[Shoppinit]

Try connecting the ground side of the sensor directly to a known good ground.

Could be a duff sensor, of course.

What makes you think it should be 12V? Are you not getting a good speed reading?

[Bowers155]

Sensor is fine, also earth from sensor is good, also check plugged and unplugged, gives same result at dash panel so had to be at the dash or before dash some place? Also has to be 12v because it’s inductive speed sensor? Plug ive referenced it off an Audi similar age with same sensor.
If when the engine loom was plugged in (whilst checked at dash) was 8.3 but when unplugged was 12 would indicate that it’s a sensor or wiring issue from dash to sensor?
I have no vehicle speed at all btw 🥲
Thanks in advance

[Shoppinit]

So no speedo? Have you checked the gearbox output speed sender with VCDS?

[Bowers155]

Pretty sure when I tested it before it’s just stayed at 0mph