Fog Light Switch

[damol]

Help

My 1999 Chimaera has just failed it's MOT as the fog light switch is not working.

The garage claims it is a faulty switch (although not too sure myself) Does anyone know where I can get an original switch from as it seems to be a hard part to source (it is the new aluminium switch)

Any ideas on what other causes there may be?

Thanks

Damian

[StreetDragster]

I would first check the bulb!

Then check to see if there is +12v at the bulb socket

If there isn't i would then check the switch, to see if that is switching properly and is there 12v to that when there should be.
Does the 'ring' light up red with the switch depressed?

EDIT- Forgot to say, that when i looked at the switched on my car, they appear to be like standard PCD mounted components avalible from maplin/cpc/rs components or similar, with a fancy adaptor and machines to make the lovely swithes on the outside. So if you can isolate a knackered component, you should be able to replace just that part for minimum cash

Thanks

Matt

Edited by StreetDragster on Monday 15th October 15:18

[Ribol]

Have you had the stereo out recently?

You might want to check the cable connection on the back of the switch anyway.

[Cider Andy]

Did they check it with dipped headlamps switched on? It won't work with just the sidelights on, or with main beam on.

As StreetDragster says, check the lamp itself. The socket unscrews, just like a jam jar lid. Here's a photo of it unscrewed.



You may find it's a bit glued in because of the carpeting, but with enough torque it will turn.

Check the lamp and lampholder for signs of having been damp (fine white deposits on the contacts. If there are any, clean the lamp and socket with some meths or WD40 on a rag. If that doesn't work, check the connector between the lampholder and wiring loom and check for +12V (red/blue wire) and check for continuity between the black wire and a known good earth.

I've also seen a post on here where the wire in the lampholder had come adrift from its connector. You'd need to remove the rubber boot to check this, or even drill out the three rivets that hold the unit together. Both can be seen in the photo.

I doubt it's the switch itself as it doesn't operate the lamp: it returns a signal to the lighting ECU, it's in the lower dash panel behind and to the side of the radio.