Any help would be greatly appreciated as I'm a bit of an electrical dunce.

Car failed its MOT today as the headlights would not latch on main beam. I've got 3 Savage push buttons; one for sidelights, one for dipped beam and one for main beam.
Side and dipped work as expected, but when main beam is pressed the switch latches but main beam only flashes.

Is this likely to be a problem with the way the switch is wired in? I've found the relay and when I swap it for another there is no change.

As an aside, I found three relays together. One is headlights, one is fuel pump. What is the other likely to be for? I couldn't work it out by taking it out and pressing buttons. It isn't hazards or indicators as they are located elsewhere.

Thanks in advance.
Oli

Hi
was it all working ok before ?
If it was , its unlikely to be the wiring ,
sound to me like the relay if the switch is latching ok.
Try changing the relay , its cheaper than the switch.
Good luck
René

If you hold the switch down does the light stay on ?, if it does then its the switch not latching.

[Edited on 6/10/13 by renetom]

Im pretty sure that it has never latched since I have had it. This is it's first MOT with me, so haven't the foggiest what it was like last year!
As you said, I thought that the wiring would be less likely as it must have worked to pass SVA and it'd be a odd thing to randomly change.

Thanks.
Oli

i take it your headlights were on?

Yes. I may not be mega with electrics but at least broadly understand how it's wired.

There's two options one is the switch has a latch which is now not working or it operated a switching relay. The easiest way would have been the relay, type the relay numbers into google and you find a full description of their operation.

Turns out that the switch was physically latching but the electrical contacts were not. Solved with some disassembly and a quick clean of the switch.