Rev counter works but electronic speedo does not.All ready fitted new sensor

fitz3@aol.com, November 2006

had same problem it was fuse

jim london, February 2013

CORRECTION
Look in the fuse box under the steering column, fuses are in two rows
bottom row 3rd fuse from the !!! LEFT !!!! reading left to right
usually a yellow 20 amp fuse, take it out and replace with the spare 30 amp one.
Do not be confused if the fuse looks ok, it is common to have a burning mark on the leg which breaks the circuit yet the fuse looks intact.
This will restore the power to the speedo and cig socket.

Mark Readman, May 2008

This problem is most commonly caused by overloading the cig-lighter/ accessory power power socket with a mobile phone charger etc.
The problem is the fuse is underrated for power applications such as sat navs etc
How to fix :
Precautions Turn ignition off and make sure you have the keys in your pocket, or wind down a window, it can lock the doors after a short delay if you mistakenly unplug the wrong fuse and lock you out !!.

Look in the fuse box under the steering column, fuses are in two rows
bottom row 3rd fuse from the right
usually a yellow 20 amp fuse, take it out and replace with the spare 30 amp one.
Do not be confused if the fuse looks ok, it is common to have a burning mark on the leg which breaks the circuit yet the fuse looks intact.
This will restore the power to the speedo and cig socket.

google tags :
Vauxhall corsa 12v 1.0 speedometer fault, speedo fault, speedo not working

Mark Readman, May 2008

Try the fuse that drives the cigarette lighter, no lighter working then everything on dash is ok except the speedo. Strange but true.

Steve, October 2007

check the continuity of the wiring from the gearbox sensor to the speedo head and ensure that there is no break in the wires. If all is well and appears OK, a second hand speedo is the cheaper solution. depending on your level of skill you could remove the insrument assembly and look for faults on the flexible connections from the instrument plug to the speedo head itself on the rear of the cluster.

Just a thought, shine a torch inside the opening where the speedo sensor fits into the gearbox and check the mating cog exists within the gearbox itself. I have known in the past for the 'driven' gear to be damaged and not turning the sensor shaft (Rare)

Good luck

SB, November 2006