Single front fog not working

cletus

Wife has a '08 Grand scenic. Drivers side front fog was gone (at least I thought it was). Bought a new bulb, stuck it in this evening, and nothing. Passenger side works fine.

Any ideas where to start looking?

Atlantic Dawn

Do you know if it has ever worked? Any sign of damage around it?

Perhaps try another bulb in it first, could be a bad bulb.

cletus

Thanks for the reply. Tbh, not sure if it ever worked, or if she ever turned on the front fogs.

A little more info, I've swapped out the bulbs, both work on passenger side, neither work on the drivers side.

Getting a reading of 4.6ish volts on passenger side, nothing on drivers side.

Haven't checked the fuse yet, but can I safely assume there's only one fuse for both lights? Could a faulty relay cause one bulb to not light?

Or, as I'm coming around to thinking, is the most likely issue with the wiring? The plug looks ok, no scorching or anything that I can see.

Going to try and trace back to where the wiring splits for the two bulbs, see can I check continuity

HarryTheSpider

Sometimes lights have separate fuses. Check the fusebox first.

punisher5112

I would say cable or most likely corrosion of the contact for bulb....

I'd say most likely water has got in....

Take bulb out and look at bulb socket.

Then check cables and connections.

colm_mcm

4.6v on the passenger side is obviously an issue too.

cletus

colm_mcm wrote: »

4.6v on the passenger side is obviously an issue too.

What should it be pulling?

colm_mcm

cletus wrote: »

What should it be pulling?

12 or 13v

How are you measuring it?

cletus

colm_mcm wrote: »

12 or 13v

How are you measuring it?

Multimeter, both probes into the plug where the pins go, with the engine on and fog lights switched on

Edited to add: of course, I'm not thinking straight. Long day in work, I was conflating the amperage of the fuse for the fog lights (which I think is 5 amp) with the voltage it should draw. Sorry, being stupid

colm_mcm

Check the voltage to a known good ground.

cletus

So this has the feeling of a proem that might not be fixed easily, and the car is booked in for nct retest, with the fog light being one of the fail items.

Anybody know if there is a way to not have the fog lights tested, shy of actually removing the fogs completely?

This would be as a temperary measure to give me time to get the problem sorted

punisher5112

cletus wrote: »

So this has the feeling of a proem that might not be fixed easily, and the car is booked in for nct retest, with the fog light being one of the fail items.

Anybody know if there is a way to not have the fog lights tested, shy of actually removing the fogs completely?

This would be as a temperary measure to give me time to get the problem sorted

Cover both front fogs with insulating tape or likes of duct tape.

They aren't a fail item if not fitted or covered.

cletus

punisher5112 wrote: »

Cover both front fogs with insulating tape or likes of duct tape.

They aren't a fail item if not fitted or covered.

Even as a retest?

punisher5112

cletus wrote: »

Even as a retest?

Yeah should be fine. If they are not there they can't test them.

punisher5112

punisher5112 wrote: »

Yeah should be fine. If they are not there they can't test them.

Re test for fogs would only be a visual. You can rock up anytime and just ask one of the testers when they're dropping out another car. Get them before they walk back in.

cletus

Thanks for that. Brakes and headlamps need to be tested as well