Electrics: 70: Wiring symmetrical rear foglights

[StatusRed]

Originally Posted by DaveNP

Unfortunately the old threads on foglights have lost their photos, but if you want to try it take both rear light bulb holders out and do a comparison. The bulb holders are made of plastic with what looks like galvanised steel holders and contacts for the bulb stuck to them, on the drivers side there is a link to the fog light position which is missing on the passenger side.

From reviewing the old threads it seems that the C70 rear light bulb holders cannot be swapped from left to right as they have a definite shape which is a mirror image, it would expect it's still be possible if you put them next to each other to spot the difference in the metal parts.

Yep that's exactly what I did. I was fairly confident in what needed to be done I just wasn't sure if it was OK to use a bit of wire to bridge it or if I needed to get hold of this galvanised steel.

[DaveNP]

With the way the V70 units are made there's some press fitting of the 'steel' pieces and then some plastic welding to hold it in place, which would be why everyone does it with a bit of wire and a generous dollop of solder

[StatusRed]

Sorted it this evening:



Had a bit of a panic when I tried with both bulbs on it blew the 10amp fuse which I didn't quite understand.. I've replaced it with a 15amp fuse and now both rear fog lights are working, did anyone else experience this?

[StatusRed]

The end result by the way

[Cookeh]

So if I'm understanding this correctly, one is soldering one end of a wire to the metal frame and running the other end into the bulb holder? Does that end need solder or does it simply need to contact the bulb?

Apologies for all the questions, I'm far from intelligent.

[Luxobarge]

Originally Posted by Cookeh

So if I'm understanding this correctly, one is soldering one end of a wire to the metal frame and running the other end into the bulb holder? Does that end need solder or does it simply need to contact the bulb?

Apologies for all the questions, I'm far from intelligent.

If you want it to last and be reliable (and safe!) solder both ends.

[StatusRed]

Originally Posted by Cookeh

So if I'm understanding this correctly, one is soldering one end of a wire to the metal frame and running the other end into the bulb holder? Does that end need solder or does it simply need to contact the bulb?

Apologies for all the questions, I'm far from intelligent.

That's right yes, it just needs to have contact with the bulb. You could solder it optionally but that will mean having to desolder at least the bulb end or metal frame end of the wire if the bulb ever blows.

In my example the wire is wedged in the bulb holder making contact with the bulb. I've driven the car around and it hasn't come loose so seems good.

[DaveNP]

If you've got an 850 or V70 the contact should be there already and you bridge the missing link, it appears the C70 doesn't have a contact hence StatusRed running the wire straight into the bulb holder, if it were me I'd use a piece of very heavy gauge copper such as one finds in the ring main to an oven which would hold it's shape better.

[PNuT]

Two fog lights are twice as bad as one!

Has any one done the electrical sums to make sure this is safe?

[StatusRed]

Originally Posted by DaveNP

If you've got an 850 or V70 the contact should be there already and you bridge the missing link, it appears the C70 doesn't have a contact hence StatusRed running the wire straight into the bulb holder, if it were me I'd use a piece of very heavy gauge copper such as one finds in the ring main to an oven which would hold it's shape better.

Ah that's interesting that on the V70 and 850 the metal in the bulb holder is already there..

I did consider a single core wire would hold the shape better and I agree, but I used the same wire on my S40 to tap the foglight so used the same again on the C70 and once it worked I just left it alone.

Originally Posted by PNuT

Two fog lights are twice as bad as one!

Has any one done the electrical sums to make sure this is safe?

What do you mean? Each 21w bulb on a 12v circuit will be 1.75amps.