Hi Guys

 

Speedometer did not work and the associated drunken fuel gauge.

 

I knew the gremlin was in the loom but I did not really want to strip the wiper assembly etc to get to the loom connectors

 

I pulled the 3 pin plug off the gearbox sender,  the pin at the square of the plug is 12v feed, middle pin is sender to the

speedometer and the pin on the rounded end of the plug is ground.  After a lot of trial and error testing I found the feed was only showing 7.8v,  this I found was the problem when I hot wired the feed straight off the battery the speedometer came back to life and the fuel gauge stopped lurching on corners

I will snip pin 5 on the 32 pin feed plug at the instrument cluster if this reads 12v I'll splice into that, if its still 7.8v I'll run a fused feed with a switch to the sensor from battery.

Can just stick a pin through the insulation and test rather than having to snip. Or get a probe or pin down the side of the connector.