Suddenly no rear fog lights

Talk about the 406's electrical system, what wires do what, how to add extra functionality, etc.

Moderator: Moderators

Post Reply
PeterN
3.0 24v
Posts: 1501
Joined: Sun Mar 04, 2012 7:04 pm
Location: Charmouth, Dorset

Suddenly no rear fog lights

Post by PeterN » Sat Jun 08, 2019 1:17 pm

My friendly MOT tester pointed out that I had one very bright tail lamp and the other one didn't work at all, simples I thought. The bright one had the wrong bulb in it, they use half a stop/tail bulb and this had a 21w lamp fitted. The other side was severely corroded so I fitted the assembly from the scrap car, I now have perfect tail and reverse lights but no rear fogs although they were working before I interfered.

There is no voltage on the lamps although the front ones are working OK, fuse I thought but apparently not, if I short the stoplight feed to the fog lights they both light up so apparently no problem with the rear wiring unless its the body to tailgate loom.

Any one had this problem?

Peter

frog
2.2 16v
Posts: 247
Joined: Sun Aug 24, 2014 12:18 pm
Location: Netherlands

Re: Suddenly no rear fog lights

Post by frog » Tue Jun 11, 2019 7:49 am

Did you ever see the rear fog lights working?

If it is not the fuse, it could be the relay (in the BSI box). The front fog lights seem to have an extra relay in the BSM (engine compartment fuse box), but for the rear fog lights there is a relay only in the BSI box.

Otherwise it may be the stalk switch. Or a broken wire in the loom but that would be far fetched.

I can look up the electric schematics in SEDRE if you like. I would need to know your DAM number (or VIN number so that i can look up your DAM number).
Current "fleet":
2003 406 Estate 2.0HDi 110 - 7 seater
2001 Citroen Saxo 1.6i 8v 100

Previously owned:
2000 406 Sedan 2.0 HDi 90
2000 406 Coupé 2.0i 16v 138 - Riviera Blue

PP2000 user, can help with faults / diagnostics in the Netherlands.

PeterN
3.0 24v
Posts: 1501
Joined: Sun Mar 04, 2012 7:04 pm
Location: Charmouth, Dorset

Re: Suddenly no rear fog lights

Post by PeterN » Tue Jun 11, 2019 10:54 am

Thanks for the reply. Yes they were working, or at least one was prior to me changing the o/s lamp assembly, after a number of tries, I took the dustbins down to the farm last night, tried the fog lights but only the front ones came on again although the rear ones were indicated as 'on' on the panel, when I got back to the house I tried them again - and they were working. :? :frown: :oops: :?: -- 8)

Peter

frog
2.2 16v
Posts: 247
Joined: Sun Aug 24, 2014 12:18 pm
Location: Netherlands

Re: Suddenly no rear fog lights

Post by frog » Tue Jun 11, 2019 11:36 am

PeterN wrote:
Tue Jun 11, 2019 10:54 am
when I got back to the house I tried them again - and they were working.
Perfect! Maybe it was the built-in electronic fog sensor that did not detect enough fogginesss :cheesy:
Current "fleet":
2003 406 Estate 2.0HDi 110 - 7 seater
2001 Citroen Saxo 1.6i 8v 100

Previously owned:
2000 406 Sedan 2.0 HDi 90
2000 406 Coupé 2.0i 16v 138 - Riviera Blue

PP2000 user, can help with faults / diagnostics in the Netherlands.

PeterN
3.0 24v
Posts: 1501
Joined: Sun Mar 04, 2012 7:04 pm
Location: Charmouth, Dorset

Re: Suddenly no rear fog lights

Post by PeterN » Wed Jun 12, 2019 10:58 am

.. obviously the fog at the rear is different. :wink:

Peter

Post Reply