Hi all, I have changed all the switches to toggle switches using a large off/on/on one for the side lights/dipped headlights and a small off/on for the main beam.

The problem I'm having seems to intermittent. the main beam works fine on it's own (switching the switch to on), but sometimes when I switch the dipped headlights on the main beam is on even though the main beam switch is off. Then when I switch the engine off and restart it, it is fine. Side lights are fine!

Any ideas??

Sounds like you may have an earthing problem?

Have a good scout round the engine bay and make sure you don't have a loose earth strap or have one thats become corroded.

or relay remaining latched in?