Accepted Answer

hi there, there is no relay for this system. there are 3 wires at the sensor. the black wire is the 12v supply, the brown wire is the earth and the blue/red wire is the signal wire to the speedo. if you remove the sensor from the gearbox you can turn it by hand and at the same time check for a signal voltage being generated by the sensor. you should also check the drive pinion in the gearbox incase it is damaged, loose, broken etc as this too could cause your fault. if all checks out ok then you need to remove the instument cluster to check the signal voltage at the blue/red wire in the multiplug. if this is ok then the fault is either with the instrument circuit board or the speedo itself. if there is no signal at the blue/red wire then it needs to be traced back through the harness to find the break. hope this helps. cheers. davie.

Expert:	Davie
Pos. Feedback:	100.0 %
Accepts:	281
Answered:	12/8/2008

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