Xantia foglights not working

This is the Forum for all your Citroen Technical Questions, Problems or Advice.

Moderator: RichardW

Post Reply
Fox
Posts: 193
Joined: 12 Oct 2002, 02:59
Location: United Kingdom
My Cars:

Xantia foglights not working

Post by Fox »

Hiya,
Bit of an odd one this. Foglights on the Xantia dont work. Been doing some testing which involved removing the lamps and testing the connector, and have so far got the following information:
The connector has 12v flowing through it when the lights are switched on, as indicated by a Multimeter. The connector has a good earth. However, the connector will not illuminate either the lights, or a test bulb. The lights have been tested on another power source, and work fine.
Any ideas?
User avatar
AndersDK
Posts: 6060
Joined: 21 Feb 2003, 04:56
Location: Denmark
My Cars:
x 1

Post by AndersDK »

Pretty sure that the "OK tested 12V feed" is far from OK. Try test again with multimeter, when bulbs are connected. You may then see a very low feed voltage, or a strange high volts reading on the earth wire, either indicates a weak (corroed) connection somewhere. May even be a dodgy/loose fit fuse.
Fox
Posts: 193
Joined: 12 Oct 2002, 02:59
Location: United Kingdom
My Cars:

Post by Fox »

Tried replacing the fuse, to no avail :( Will try the other ideas. All the wiring is wrapped in the plastic tubing, so fixing this one could be a problem :(
jeremy
Posts: 3959
Joined: 20 Oct 2002, 16:00
Location: Hampshire, UK
My Cars:
x 2

Post by jeremy »

I agree with Anders. It is possible for a supply with a high resistance to show a healthyish voltage on the very high resistance of a meter but as soon as it is subjected to a real load such as a light, the high resistance shows up. Try testing the feed using a bulb and see if it still works. The actual wire is unlikely to be at fault, but rather it is probably a connection, so start tracing them and test them all with the bulb until you find the problem.
How have you tested the units themselves? If you have only used your meter it may be worth putting a battery on them and getting them to light first. Next worth trying another earth - ie direct connection to battery or similar.
careful reading of you meter may show up the problem as often if there is a high resistance in the circuit the voltage will show as slightly low (ie a couple of decimal places) the problem here is that the available voltage drops with the length of the cable so you can't expect the same voltage as is present at the battery to be available everywhere else.
jeremy
Fox
Posts: 193
Joined: 12 Oct 2002, 02:59
Location: United Kingdom
My Cars:

Post by Fox »

Yes, I have tried the feed with a bulb, it wont light, and I've tried the lamps on another feed - they work.
As far as connections are concerned, how many are there bar the one where you connect the two foglights to the main supply under the bumper?
jeremy
Posts: 3959
Joined: 20 Oct 2002, 16:00
Location: Hampshire, UK
My Cars:
x 2

Post by jeremy »

You will have to check the wiring diagram for the number of connections but remember the wireing will run to the switch on the dashboard and is probably interconnectd with the headlights to ensure the lights operate on dip or full beam or however they are set up.
jeremy
User avatar
JamesQB
Posts: 375
Joined: 13 Aug 2003, 18:01
Location: North Wales, United Kingdom
My Cars: Citroen Xantia 1.8 - I miss this car a lot.
x 5

Post by JamesQB »

Did you try connecting the positive foglight feed to the bulb but using a wire going to the battery negative so that you have a direct earth connection, rather than using the foglight negative wire?
You can easily find out which wire has the high resistance (positive or negative) with this method. If you use foglight positive and battery negative on the bulb and it lights, then you have trouble with the foglight negative wire but if bulb only lights with positive from battery and foglight negative, then the positive wire has or leads to the trouble.
I had similar trouble with headlights on an Escort, 12V was happily there according to meter. Turned out to be the fuseholder, the solder around the legs of the holder had cracked terribly and was just making contact to the PCB, enough to provide 12V but no current behind it.
Post Reply