Suspension: V40 dipped beam not working

[Drjvolvo]

I have 12 volts to the dipped beam connector terminals, I have used bulbs Iknow are ok bu t cannot get the light to work. The side light and main beam work ok. Fuses are ok. This is second headlight unit I have tried and both have been exactly the same. Frustrated and confused! Help please!!

[clarkey1984]

Classic symptoms of a CEM fault, the CEM is a control unit that does the lights, wipers, plus some other stuff, someone more knowledgeable will no doubt be along soon as I don't really know much about them.

[martin93]

What year is your car? Just incase it's a model without a CEM.

Martin.

[druid]

Gatos is your man for this, not very dear just needs to know if you have fogs and the wiper. If you get an S one it wont be set for it.
It's under the dash, that bit under the steering wheel agree you keep a cloth? That's the bit you need to undo for access.

[martin93]

... if it's a phase 2 (or 1.5) with a CEM. Phase 1's just have an ignition controlled relayed feed to the headlight units, and then earths through the headlight and main beam switches depending on their positions (roughly).

IF it is a later car, then yes it is most likely a fault with one or both of the soldered on relays inside the CEM which is a common issue. You can indeed replace the whole CEM with one of the same specification as yours, or if you're steady handed with a soldering iron there is a guide somewhere showing you how to open up the CEM and replace those relays.

Martin.

[baldmosher]

You can find the CEM diagrams on here and I've got the correct relay if you want one. I bought a couple of spares from RS as they were only a couple of quid.