Hi Chaps, looking for a bit of help here. My speedo stopped working, (along with the trip and odometer) but all the other dials work. Here's what I've tried so far;

1) taken the old speed sensor out of the gearbox and tested it with a drill,,,,,nothing in terms of voltage coming out of it.
2) fitted a new speed sensor, nothing showing on the speedo when driven.
3) tested the new sensor whilst connected to loom with a drill, again, nothing showing on the speedo.

I'm now assuming that either the connector into the speedo has come loose, assuming its a dedicated connection OR there's a split in the wiring loom somewhere?

Any suggestions as to how I can further fault find or what to do? Am I missing something here? How easy / difficult is it to get to the back of the instrument cluster and how do I "test" when I'm there?

Thanks

http://files.homepagemodules.de/b561340/a_7_2b9a45dc.gif

Holmezy

When you say there is no voltage coming out of the speed sensor, did you apply a voltage to it? They do not generate voltage, I not seen the exact one on an L200 but every other one I have worked on has 3 wires. a 12v supply, an earth and a switch voltage output that simply pulses the incoming voltage

You can also check the wiring loom that goes around the back of the gearbox, they are known for chaffing through the wires giving various issues

Saudirick,,,,,,ahaa,,,,,I'm obviously got the wrong idea? My sensor has 3 terminals. Positive, negative and one that I think is denoted by a "p" if I remember (I'll have look when I'm next under the truck!!). I always assumed that the spinning connection generated voltage which causes the clocks to work,,,,??? If this is the case, and it sort of makes sense now, my drill test was done with the sensor connected to the loom and the engine running, but still nothing? Is there a check I can do on my sensor? I think it may be the loom and I assume it will need splicing / bridging? Don't suppose you know how to get the clocks out of a 2007 l200 do you, just in case its the connection at the back?

You can do a simple test of the sensor with a multimeter. connect a battery positive to the sensor positive terminal, even a PP9 9V battery will do, battery negative to sensor negative, multimeter negative to sensor negative and multimeter positive to the third terminal. spin the sensor slowly by hand and you should see the voltage go from 9v to 0V either twice per revolution or 4 times per revolution (dependant on sensor type)
Sorry I dont know how to get the clocks out

Not sure if this is still an issue for you.

I had this problem. I lived with it for a few years using a sat nav to judge speed by and pass mot. Finally last year when I've had lots of time to fill I started investigating further than I had previously (I'd tested things similarly to you, got a new sensor etc etc). I checked the continuity of the sensor cable that connects the sensor to the dash. This cable had a break somewhere - instead of finding break and repairing I just installed a new cable, routing it the most sensible way.

Strangely over the 3 mots the mileage has decreased by a mile a year - very bizarre, so it looks like I've been fiddling my dials a bit too keenly!