I'm very close to finishing the wiring off and seem to be one or two fuses spaces short and it got me wondering. I have 2 fused supplies to the high beam and normal beam relays respectively and then 2 more fuses located on the lines from the relays to the headlamps. Do I need the fuses on these lines or would the ones serving the relay suffice?
It just means that I could free a couple of fuse spaces up in the fuse box for the fog light and horn.

I'd have been happy with just the fuses supplying the power to the relay (the high current side) any short will affect the whole supply so another two fuses after the relay don't actually serve any porpose. I'd also fit fuses that are rated below that of the relay so that doesn't go up in smoke.

[Edited on 5/8/08 by Mr Whippy]

Sounds good to me. Couldn't decide if it would or wouldn't. Means I should be able to cram everything in the fuse boxes I have. Cheers.

The answer very much depends on where in the relay circuit the fuses are and whether you're running switched earth or switched positive.
If you've got switched positives running to the relay and you're switching the +ve supply to the lamp via the relay then you could put a fuse in the -ve and fuse both the relay and the headlight.

You're getting complicated now Ben. I am switching positives yes. As long as things are safe and ain't going to set on fire I'm happy with that

Aha! Then it's easy. you can earth the relay and the headlights via the same fuse. Job done...