Citroen XM Forum

OK I give that a try today and let you know what happens

Tried that no luck, the problem must be deeper

Just use a test lamp to go back in the wiring.
Test to see if the relay has:
Gnd
Batt+
A signal supplied by the lights switch, a feed to the headlamp bulbs and they also have a Gnd.

All these tests can be performed with a test lamp, or multi-meter.
To test the feed to the lamps and their Gnd, just connect a test lamp to Batt+ and the lamp feed, at which point if the circuit is complete the test lamp will illuminate.

Feed back what you find and we can help you further.

Given that both electrical issues are related to the front of the car, is the fan console unit actually connected?

Fan console interior is connected and working, but I do have the main rad fan relay pulled for the moment

That won't be affecting the lights.

I think the problem is deeper, might be a short somewhere, I had done the relay test you suggested, one dip light came on, when coming back to try it again it would not come on, what would be handy is wiring diagram that follows how it is wired up in the car, including the looms where all the wires bunch together

Just follow the wiring diagram you have, it is complete and accurate for your car.

Use a multi-meter, or test lamp and tell us what you see on each relay pin. Both lamps should be connected together, so if one works and the other doesn't either the bulb is blown, or the contacts are poor, or a feed wire, or Gnd is broken.

Got one dip light working, the driver side, the problem for that one was up near the ignition, I moved some wires, and one lamp started to work and the dip light warning lamp came on the dashboard, the rest still the same

Southerneruk wrote: Mon Jul 20, 2026 11:07 am This is giving me a headache, notice that the dip warning light on dash is not lighting up, when I jump the relay only the driver side dip come on

That makes sense, the power for Dip beam comes from the ignition, passes through the lights switch and feeds the relay and the dashboard indication.
The Ignition switch connector is the 2 pin, brown connector, Pin-2. Diagram shows [2M2] wiring colours are in French. The same format applies to all connectors.

Do you have a test lamp, or perhaps a test meter? A test lamp is all you need for this. If you don't have one, either buy one or make one from a car bulb and a couple of bits of wire. An old headlamp bulb would be good as it will pass more current so test the wiring and connections under greater load.

See attached circuit diagram and layout sheet. I've also attached the numerical index for all the components, which is already in the Series 1 circuit diagrams thread.

All electrical devices in this instance, need a positive voltage and a return to the battery, called Ground (Gnd) to function. This is called a circuit.
Faults can be either the Positive supply, the Gnd return, or the device itself.

Looking a the circuit diagram it shows the dip beam bulbs (486 &487) are fed by a single relay (825). The cable splits after the relay, so should receive the same positive feed.

The lamps have to have a Gnd return to the battery. The Gnds are separate, but both terminate at m1, which is the Rh inner wing. Any body Gnd connection will work as long as it can pass sufficient current.

First test your test lamp across the battery to ensure it works.
Next connect one lead of the test lamp to Batt +ve and the other to the body Gnd to ensure it is sound, if good then connect to the headlamp bulb Gnd connection.
Another test for the headlamp bulb Gnd would be to switch on main beam (502, 503), as they and the sidelights (492, 493), share the same Gnd connections.
If main beam doesn't work, try "flash" function, which uses the same wiring as main beam, but a different switch and power feed.
Once you have proven the Gnd side is sound you can forget about it and move on.

One test for dip beam feed would be to switch on the rear foglamps, as they only work on dip beam, but as you now have one working and the dashboard indicator working, we know that is sound.

Switch on the Dip beam, at which point you have reported only one dip beam lamp illuminates. This proves that the relay is being fed Batt+ and the cabling to to the working lamp is sound.
That leaves the fault to be either a cable fault or bulb fault.
Either connect the test lamp to the non working bulb +ve feed and Gnd. If it lights the bulb is blown, if not the cable is broken, or has a bad connection.
You could try swapping the bulbs over to see if the fault stays the same side, or moves with the bulb.


Note, on the diagrams all wiring colours are in French, the index is in the Series-1 circuit diagrams thread. viewtopic.php?f=8&t=10268

Work your way through those checks and tests, note carefully what does/doesn't work and any test results, then report back.
The more accurate information we have, the easier diagnosis becomes.

The Exterior lights wiring diagram is two pages: page 1 is the wiring point to point diagram, page 2 is the physical layout diagram. Indicator wiring diagram now attached. The side repeaters, (500, 501) are just spurs from the front indicator wiring, (488, 489).
the issue is likely to be corroded bulb, or connector onto the repeater, contacts.

Testing the light bulbs was the first thing I had done, then look for a blown fuse, they all seem OK, will test them again just in case, will also recheck all the grounding points, I do the side wing indicators at the same time.
I do have a multimeter somewhere, It still could be up around the key ignition I have had problems in that area before

Been a good day, cleaned two earthing points, and though I do a quick check, no change, wiggling the stork to the lights and I notice dip came on both sides, the wing indicators turning out to be the wire on the bulb being to flat no longer making contact on one side the other side it might be the wiring needs looking at