Just getting my Murena ready for MOT, headlamps come up and on OK if on main beam but don't come up if on dipped beam. Going from main to dip beam makes the headlamps go down and off.
Any idea if there is a relay controlling this and where it is? Is this the white thing under the cover on the right hand side looking forward in the front compartment?
No, that is the vacuum valve that switches the double acting servo to lift or lower the lamps.
If you check the wiring diagram that I left with you Zac, you will see that there are four relays on the circuit board, one for dip, one for main, one for driving lamps and one for the electric windows.
You can check the relays and feeds even without taking the circuit board out, as the contacts are right where you need them amongst the fuses. However, I doubt a relay has failed - they rarely do, it is more likely a poor edge contact or column switch contacts. Think about it - when you switch on the headlights, two things should happen - the lights come on AND the headlamps lift. If neither happen then it is not the relay. The relay only powers the lamps on, so if the relay had failed, they would still have lifted. If they fail to lift but the lamps come on the fault is with the lifting system. If both do not happen, the fault is either the switch or the feeds from the switch are not getting to the circuit board. If you check my report on your first invoice you will see and maybe remember I stated your circuit board was not in the best condition and could do with replacing too.
Normally you have the column switch in the higher position and when you turn the knob on the end, the first turn brings on the sidelights, the second turn should bring on and raise the headlights. However, if you put the column stalk in the lower position, then the first turn of the knob brings on both sidelights and headlights at the same time. Second turn of the knob switches to main beam. Try that and see if you get any different result.
Roy
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