Retrofitting fog lights raises headlight switch wiring question

Valpen

Valpen

Member
I am adding original front foglights to my FSI 1.6, and have sourced the lights, grills, wiring harness (from eBay Germany - search for: Audi A2 8Z NSW Nebelscheinwerfer Kabelsatz Kabelbaum Adapter fog cable harness) and the main headlight switch (with the front foglight position).
The very brief installation instructions that came with the wiring harness / loom said to just add the 12+ wire to the number8 contact in the light switch plug (and find a suitable ground/earth in the engine compartment). Which looks to be a working solution.

My question, is can the main headlight switch handle the current for the front foglights directly (2 x 55W halogen bulbs) or should I use a relay to provide 12+ to the foglights.
In addition, I am not sure where in the electrical lighting circuit the fuse for the foglights (number35) is when compared to the switch and the lights (so should I also have an additional fuse in the circuit after the switch and before the bulbs?).

Thx in advance for your advice.
 
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I am currently doing this job but making my own loom. I have a relay and a fuse on the power line so that I know its done correctly.
I'm sure someone will be along with the knowledge you need to help you, but if you're not sure why not add a relay anyway, and an in line fuse?
 
I am not sure that the factory fitted front fogs have a relay? If that is the case then you wouldn’t need one.

I guess it never harms to use one but it is extra wiring.

Also is there a headlamp relay? They use the same bulbs as the fog lights. So if they do t have one you should be ok without. But I am no auto electrician.

Just a few things to consider logically.

Steve B
 
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bretti_kivi said:
authoritative: you do not need to add a relay or a fuse, they're already correct. Use pin 8.

More details and authoritative pics here: http://www.leibbrands.de/NSW_nachruesten.pdf

- Bret
Click to expand...
Very nice helpful info/photos in the link, thx Bret.
My german is quite "thin", but as I understand it from the photos, they are saying to add the 12V+ connection on the back of the fusebox (as indicated), not on the back of the headlight switch...(where I found the pin8). Correct?
EDIT - I guess it is not the back of the fusebox, but rather the connecter-block at the bottom of the A-pillar (as indicated)... thx Andrew.
 
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Hi,

my experience of 3 A2's of different model years is that the actual pin numbers of the connectors in the bottom of the A pillars changed frequently.
In my 2001 1.4 petrol, the fog lights are on pin 15 for example.
What is common however is the wiring colours. The fog lights are always driven by the red wire with the purple stripe. It may or may not be in pin 8, 15 or indeed somewhere else.

All A2's are wired in the dash for fog lights. A car without fog lights fitted in the factory will have the correct connections on the light switch plug but a switch without the fog light position. This includes the power feed. The switched feed from the light switch will end in the connector in the passenger foot well A pillar. The missing loom is between there and the engine bay. There isn't any need to "beef up" the feed unless you are running non-standard fog lights with a much higher power draw than OEM.

regards

Andrew
 
If it is the case that we just need a power wire from the passenger footwell to the fog lights, can someone suggest what size wire is required? Would 1mmsq be ok?
 
The red wire with a purple tracer which goes to the front fog lights from terminal 8, is 1.5sq mm on the A2 wiring diagrams. It branches to 1sq mm for the individual lamps.
I am about to do this mod on my sons 2002 Polo 9n, trying to suss out the connectors.
All the best,
Matt
 
I was encouraged by this thread to see if the wiring up of my retrofitted fogs was as simple as described. i.e. no need for relays and wiring from the switch. Looking at the connector block on the passenger side 'A' post (rhd vehicle) and the block described in the link that Bret gave the grey plug is not present. I wondered if as Bret has a lhd vehicle wheher mine would be on the other side but I cannot identify it on this side either.

This pic is the passenger side:
IMG_20180309_154144.jpg


This pic is of the drivers side
IMG_20180309_155943.jpg


Any ideas as to which is the equivalent plug?
Geoff
 
Hi,

as I mentioned in my previous post, Audi seem to have kept changing the layout of the connectors on the A pillars. None of the A2s I own or have owned have matched each other or the Audi schematics in terms of connector type or pin layout. The wires are the same, they just aren't in the same place.

Two examples of the passenger A pillar:

DSC04083s.jpg


DSC03249s.jpg



The top picture is a 2001 model and the bottom one a 2004.

The bottom one looks like your car. I have checked my notes and the fog light connection on this one was pin 4 of the 10 pin connector. Unfortunatelly I didn't write down the colour of the connector. You could try the blue one first as that's unplugged in the picture.

It should be easy to find the right wire. It is on the passenger side. The wire will be red with a purple stripe.
Once you have found the red / purple wire, you will notice that the pin position of the connector on the other side is just an empty hole.
If you have changed the light switch for one with the fog light position you can also double check with a multimeter but I am sure there is only one wire with that colour combination.

regards

Andrew
 
Andrew, as you point out the plugs seem to change through the model years. I can find no trace of a red wire with a purple tracer on any of the plugs. I am wondering whether they even dropped wiring from the light switch to the connctors on the runout models. I only have 4 connector blocks at the passenger A post. I will have to look to the light switch itself for the presence of this elusive red/purple wire!
I am sure Timmus is chuckling up his sleeve if he reads this.
Thanks for your help though.
Geoff
 
Sootywg said:
Andrew, as you point out the plugs seem to change through the model years. I can find no trace of a red wire with a purple tracer on any of the plugs. I am wondering whether they even dropped wiring from the light switch to the connctors on the runout models. I only have 4 connector blocks at the passenger A post. I will have to look to the light switch itself for the presence of this elusive red/purple wire!
I am sure Timmus is chuckling up his sleeve if he reads this.
Thanks for your help though.
Geoff
Click to expand...

Hi,

I can't remember which side of the connector the interior loom goes, it could be the side fixed to the car, the back, and so difficult to see without unfixing the connectors.

As you say, looking at the light switch end is a very quick and easy way to confirm whether the wiring is there to be found. The fog light connection is pin 8 marked "NL" on the back of the light switch. That wire should go straight to the A pillar connector.

happy hunting.

Andrew
 
Confirmed that the red wire with a purple tracer is present on the switch plug, so re checked the plug blocks at the passenger A post and yep pin 4 blank on the removable plug side has the red/purple wire at the back of the fixed side. So thanks for suggesting that might be the case. Strange though that the 'blades' are the live side of the connectors.
Do you by chance know the correct type of contact/terminal connector that is needed to be inserted into the plug?

Thanjs Geoff
 
Sootywg said:
Confirmed that the red wire with a purple tracer is present on the switch plug, so re checked the plug blocks at the passenger A post and yep pin 4 blank on the removable plug side has the red/purple wire at the back of the fixed side. So thanks for suggesting that might be the case. Strange though that the 'blades' are the live side of the connectors.
Do you by chance know the correct type of contact/terminal connector that is needed to be inserted into the plug?

Thanjs Geoff
Click to expand...

Hi Geoff,

I have gathered some information regarding this.

Yes, the blade (male) connector side is on the the dash loom which is where the supply current comes from. the receptacle (female) side is on the engine bay loom. You might think they should be the other way round, but that's how it is!

On my 2004 FSI I have a blue connector with pin 4 used for the fog light connector. This is a picture of the engine bay side of the connector. You can see the two wires for the individual runs to each light from the same terminal.

DSC05245.jpg


Audi don't sell the crimp terminals on their own, instead they sell "repair wires" which are basically a short length of wire with the terminal pre-crimped. As you want a much longer run to the lights if you had one of these you would need to join this to the rest of the run.

The connector used in the A2 for this is manufactured by TE Connectivity under the AMP brand. I wanted to look up the manufacturer's part number which is printed on the side but it looks like TE no-longer make this part and I was unable to find details for it. Although newer VAG cars still use this connector, they look slightly different and may well be produced by another manufacturer.

The Audi connector part numbers are:

1j0 937 743 D - spades, dash loom internal side

1j0 937 733 D - receptacles, external engine bay side - where the fog lights need to go.

After some research I found an interesting thread regarding making up looms and sourcing the parts on the TDI Club forum site:

http://forums.tdiclub.com/showthread.php?t=245319

One interesting piece of information from this is a reference to a UK supplier of automotive electrical parts. They sell the individual crimp fittings to go into these types of connectors. The range is listed here:

http://www.vehicle-wiring-products.eu/section.php/206/1/terminals-to-fit-mouldings

I found that site after looking at the car so I can't identify the correct one from the list without re-checking, but it should be just a question of checking the size and orientation of the existing receptacle and ordering the equivalent from the supplier. The terminal can then be attached to the new wiring and inserted into the connector.

When inserting additional terminals into the connector you need to release the locking mechanism. This is the different coloured plastic part which slides partly out one side when pushed on the other. Its the white part on the blue connector. Once unlocked, its possible to insert the new terminal from the top. The terminal then clicks into place due to the two sprung lugs.
If you want to release a terminal to extract it, you need to slide to release the lock and then release the two lugs on the terminal. There is a special tool with two prongs which is inserted either side of the terminal from the mating side which push back the lugs to allow the terminal to be withdrawn.

Regards

Andrew
 
Andrew. Thanks for the detailed post. I can confirm all that you have said. I got there the hard way though! Not knowing the correct pin part number I purchased a 'repair connector' with what I hoped had correct female pins in, determined from visual inspection. I expected to be able to remove the pins with the use of the appropriate pin removal tools. I was stumped when they would not extract, it took me a while to realise that the white plastic insert is an additional locking mechanism to prevent strain when inserting the connector. Likewise inserting a pin requires this insert to be depressed. Tom (Timmus) suggested that thecorrect pin number is 000 979 242 which certainly seems correct when I compared the pins I bought with those in this link:

https://www.ebay.co.uk/itm/10PCS-00...e=STRK:MEBIDX:IT&_trksid=p2060353.m1438.l2649

All now installed and working Fogs (feeding the loom through the bulkhead was another story!)

Geoff
 
Hi, just to add my findings to this thread.
I have a 2001 51plate 1.4 tdi A2, it is a rather strange spec which I suspect was due to it being a demonstrator for Hull Audi, ie opensky and five seater, but no climate control or fog lights.
I quiet like the look of the fog lights on the A2, it just kind of finishes it off at the front end, a few months ago I bought a set of fogs with the trim panels and I also bought one of the Auto light switches from China, so in theory apart from some wiring I'm all set to go
So enlightened by the above thread I removed the passenger side trim panel and hunted for the Red wire with purple trace, however having removed the socket holder from the body to provide access to the incoming wires there was no wire, so I next removed the light switch, located the NL pin and sure enough there is no wire connected to it, just an empty hole in the connector block
I probed it with a multimeter and there is 12 volts present when the switch is pulled out, so I now need the crimp terminal that suits the light switch
The next question is do I need to fit a fuse between this wire and the fogs, or is the feed into the switch already fused ?
If anyone could spready any light on the above question I would be greatful
It would appear that not all A2 are pre wired for fog lights into the A pillar connection points
Cheers,
Paul
 
My understanding is that the red/purple wire from the NL terminal on the switch runs directly to the connector at the lh A post. The fusing I believe is on the feed to the switch. There is of course no harm in having a separate fuse just for the fogs!

Geoff
 
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50923



Hi, all,

I recently fitted the front fogs and was planning on doing the wiring this weekend. I've ordered up all the connectors, cabling and heat shrink etc that's needed to do the job (I'm trying to ignore Paul's comment about standard 5 seater cars with OSS and no climate not having the lightswitch prewired for fogs but worryingly that what my car is) When I took the connectors out that came with the kit (Used) to have a quick look, I noticed that although they look identical in shape one is a good bit smaller than the other.

Does anyone know if the connectors are sided or has the guy sent me out a dud, also I take it the earth is the brown cable?
 
@depronman , no additional fuses or relays are required if using standard Audi front fogs. If indeed there is no wiring for the front fogs on the loom that connects to the lighting switch you can run the feeds directly from the switch and through the bulkhead to the front fogs. If using the original audi front fog loom you can splice that into the power cable you have fitted from the switch the other cable being the earth. Also if you are interested the auto switches have a "flaw" i.e. the tell tale for the read fog is ONLY used to indicate switch programming it does not light when the rear fog is on. This is now a MOT failure. There are now a few options, 1 a friendly MOT tester that ignores the lack of tell tale knowing the switch can not be left on, 2 swap the auto light switch back for a standard one come MOT time , or 3 my solution to the problem.

How I made my auto headlight switch pass the new MOT

The auto headlight switch as we all know does not come with a functioning tel tale for the rear fogs. This is now a mot failure ( yes some testers either know the switch cannot be accidentally left on rear fogs or do not check either way a gamble. I tried to find a way to use the existing LED...
www.a2oc.net
 
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