Intermitent dipped headlights

[crabtreegreen]

I have an intermittent problem in that the dipped beam sometimes does not work, main beam is ok. It can be ok for months then stop working only to work fine again for no apparent reason. I have had the lighting electrics checked out but no fault was found. I have just noticed that the heater fan also cuts out when the dipped beam is not working or will cut out when I turn the headlights on.
Although the car is a S1 the lighting controls are on a column mounted stalk.
Has anyone got any ideas please?
Bernie

This post has been edited by crabtreegreen on December 10, 2015 03:46 pm

[kenhall1202]

Hi Bernie,

As a start I would check the lighting relay that sits above the offside headlamp for contact corrosion (assuming of course that S1 and S2 models have a similar set up).
All the slam panel mounted relays (including the 3 on the n/s for cooling fan control) on my S2 XM have suffered from salt corrosion requiring refurbishment or replacement.

Ken

Edit

A post from "xantia_V6" related to a similar problem on the French car forum states:

"The dipped beam is controlled through one of the relays on the slam panel (right hand side of the car). Corroded connections on the relay seem to be a common problem.

The is fed from the "extra" set of ignition contacts on the ignition switch (the set that always causes S1 Xantia A/C fans to stop working), so ignition switch failure is also an option, but much less common on the XM."

This post has been edited by kenhall1202 on December 14, 2015 11:13 am

[crabtreegreen]

Hi Ken
Thanks for that. I had the relays checked out by a friendly motor electrician who couldn't find a fault there. I find it odd that the heater fan cuts out also when there is a problem with the dipped beam. Also the lights work perfectly with the ignition on but sometimes cut out when the engine is started. Its all very odd really. The ignition switch that you also mention seems to be a good one to follow up.
Thanks again for the response.
Bernie

[kenhall1202]

Re the intermittent heater fan I would check fuse F2 in the under bonnet fuse box. High current draw by the heater fan can cause the common problem of burnt fuse blade contacts. My long term solution was to fit a separate Maxi fuse and holder (same fuse amp rating but physically larger allowing better heat dissipation).

Ken

[Norman]

It might be that the under bonnet fuse box has started to melt around the F2 position and replacing the fuse box would be a good idea.

[xmexclusive]

The under bonnet F2 problem is specific to the type of fuse box fitted to Mk2 XM's.
The XM in this post is a late Mk1 not a Mk2.

The Mk1 under bonnet fuse box fuses are:-
F1 & F2 - Not used.
F3 - 30 Amp - RH Radiator cooling fan (High Speed).
F4 - 30 Amp - LH Radiator cooling fan (High Speed ) plus both fans (Slow Speed).
F5 & F6 - Not used.

This indicates that on Mk1's the car interior fan is not supplied via an engine bay fuse.

John

[crabtreegreen]

Thanks for all the advice guys, plenty here for me to check out. I have found that restarting the car (if the headlights aren't working), does the trick. Hopefully this will work out until I get some free time and a fine day to take another look. Fortunately we have another Citroen and one on order so I don't need to rely on the XM on a daily basis. Its still a beautiful car to drive though, with or without its foibles.
Thanks again and kind regards
Bernie

[beckyrachel]

My late S2 2.5TD has just started doing the same thing.
You describe restarting it as sometimes sorting it, that hints at ignition switch - but relays and fuses may equally be a problem :-/

Did you get to the bottom of it?

There is no separate underbonnet fusebox on this one ( there is on my other 2 XMs), but rattling relays caused the lights to come on - although it wasn't clear which one was the culprit so I have to wait for it to fail again (and the rain to stop) before I can change the relay carrier.

These slam panel relays are a pain.

[beckyrachel]

My late S2 2.5TD has just started doing the same thing.
You describe restarting it as sometimes sorting it, that hints at ignition switch - but relays and fuses may equally be a problem :-/

Did you get to the bottom of it?

There is no separate underbonnet fusebox on this one ( there is on my other 2 XMs), but rattling relays caused the lights to come on - although it wasn't clear which one was the culprit so I have to wait for it to fail again (and the rain to stop) before I can change the relay carrier.

These slam panel relays are a pain.

[xmexclusive]

Hi Beckyrachel

All UK 2.5 TD have the underbonnet fuse box.

For the dipped headlights the usual problem is the relay or its socket.
Relay is one of those hanging just behind the top of the cooling fan panel.
It is the single one behind the passenger side headlight.

Gabors "Circuit diagram project" gives full electrical wiring and component position for a 2.5TD.
Prints out as an A5 booklet in the same format as the XM owners manual.
Ideal to keep in the car.
Was produced from the Citroen Workshop Manual then "peer reviewed" by 2.5 owners.
Posted a link on here a while ago.

John

[crabtreegreen]

Hi Beckyrachel
I haven't really got to the bottom of the headlight problem but its definitely not the relay as these have been checked twice and is more likely an ignition switch problem I was recommended a guy in Chester who worked on XM's years ago. He recalled the problem but after all this time he could not remember exactly what was the cause or the solution. He suggested using the ignition key only i.e. no heavy house keys attached as the extra weight can lead to problems with worn ignition connections. So far that seems to have worked although I have not been using the car as much.
The problem only occurs when that car is running, i.e if the ignition is on but the car not started then the lights always work both dipped and main beam hence the thought that it has to be something to do with the ignition switch.
This, together with the untraceable central locking fault and temperamental engine warning light simply adds to the rich tapestry of being an XM owner.
Best wishes
Bernie

[DrTim]

Me too. Quite intermtteint. Next time it happens I will check if it works with engine off.

Glad to see some life here and the site problem with the main menus from a few years back seem to be fixed.

[DrTim]

OK no dipped beam with engine off and interior fan not blowing either. And the problem is hard now.

[xmexclusive]

Hi Dr Tim

Wiring layout for Mk2 XM.

This post has been edited by xmexclusive on August 26, 2017 08:44 am

[xmexclusive]

Hi DrTim

Wiring diagram for Mk2 XM.

John