Speedo Transducer V8S

[seb400]

Does anyone have any experience concerning speedo transducers?
I've just completed a body-off chassis chassis repair. While we were lifting off the body the one wire we failed to disconnect, until too late, was the speedo. The connector pulled apart, ripping out the wiring. This has been repaired, but having put all back together now the speedo no longer works. All wiring feeds to speedo work but we are unable to get any sort of signal from the transducer. We have removed it and tried spinning it with a drill but there is absolutely nothing coming from it. I'm not the wiring expert on this, my buddy mechanic is, so may not be able to answer any queries on tracing the fault. We are at a bit of a loss as to why the transducer fails to provide any response to meter or LED - any thoughts anyone....please?

Many thanks Steve

[Barkychoc]

Just been looking at the wiring diagram. Looks a nightmare as the colour of the wires out of the transducer are different to the colour of the wires at the speedo.
According to the diagram the transducer should have 3 wires, brown, black and yellow.
Black is +12V, brown is earth and yellow is the pulsed 12v output when you turn the transducer.

Have a look here!

http://www.tvrsseries.com/drawings/tvrswiringdiagr...

My speedo plays up - it doesn't work for the first half mile or so then slowly comes to life.
I keep ignoring it hoping it will go away....

Chris

[seb400]

That does seem a bit odd, as there are only two wires from the transducer, not three.
We are thinking that the fault must lie with the transducer, it's now been checked with an oscillator but gives no output. I can't imagine why it's suddenly stopped working though.

Steve

[Barkychoc]

Maybe it gets its earth from the casing then via the gearbox?
I assume it has a metal thread?

Chris