My reverse lights were flickering for a while but then stopped working altogether. Checked bulbs and fuse. Replaced switch. Crossed wires and still no light so it seems the new switch at least is not the problem. Must be loose wire somewhere but finding it very difficult to follow wire. Any help or suggestions would be greatly appreciated

Divide and conquer.

Do you have 12V to the switch (red/green wire)?

Remove the connector from the switch and put a meter across it. Do you get 0? when you put it in reverse?

Is the car a hatch or estate?

We rewired and it seemed to do the trick, for a few hours. The reverse then again refused to come on. So figured it must be whatever triggers the switch. It must be worn down. We put a spot of weld on the end of the switch and ground it smooth and hey presto its been working for two months now. Im not suggesting anyone else try this as ther is a possibility that the weld will break off into the gearbox but the alternative as far as I saw it was to open the gear box and replace the offending part there.

We rewired and it seemed to do the trick, for a few hours. The reverse then again refused to come on. So figured it must be whatever triggers the switch. It must be worn down. We put a spot of weld on the end of the switch and ground it smooth and hey presto its been working for two months now. Im not suggesting anyone else try this as ther is a possibility that the weld will break off into the gearbox but the alternative as far as I saw it was to open the gear box and replace the offending part there.

Glad you have found a work-around. Are you sure you have the right switch? There are 3 versions.

What is the gearbox code from the options label under the boot carpet (probably EGS)?

Check that the o-ring isn't doubled up. The torque for the switch is 20 or 25Nm (depends on which box it is).