Stock wiring of fog lights

[penth2o]

Ok this is going to be long & full of ignorant questions.

I apologize, I don’t know jack about electric & the schematics are killing me.

I have fogs now but would like to wire it the way the dealer did for when I restore it down the road. I would like to clean up some misc. wires under the hood for later.

1974 Tii.

I have fog lights the way my brother in law set it up. It works and has worked for 30 years.

FOGLIGHT SWITCH

From reading online or somewhere I take it the 4th opening on the relay bracket was left open from BMW incase you got the optional fog lights. so I guess my brother/PO used that for the relay on the fogs.

From reading or looking at the schematics I see that there is a fog light connector on the harness up by the battery on the front cowl.

Looking at this (I may be wrong as it's confusing) I should be able to connect my stock fog switch on the dash to the stock wiring for the fog lights like the dealer would have shouldn't I ?

From what I can see is a white/violet wire coming from the pass headlight going to the fuse box with a connector on the front cowl. (blue line in my diagram).

Then it exits the fuse box (green line) & goes to the relay closest to the driver (excluding PO's relay 4th one) From there it goes to the pass headlight.

Here come the questions:

1: Should I give this up & take it to an auto electrician. I can do most but electrical confuses me. Is this doable for the average Joe. (I'm a quick learner)

2: Why do they have a tap or connector for the fog lights on the harness that goes to the headlights. Wouldn't it make sense to have a connector that goes to connectors by the bumpers for fogs. (plug & play)

3: They always say use a relay. According to this diagram the wires that they say to tap into for fogs go to the third relay. Why would BMW leave an extra space on the relay bracket for a relay for fog lites if the wiring is already going to the 3rd relay.

(or is that 4th space on the bracket not for fog relay& I was mis informed).

4: Does anyone know how this can be done. I have no options for help but me. My geographical location puts me in the sticks. I can take it to the city if this cannot be done via web.

5: Can I leave the fog switch like it is. one wire connected to the fuel pump wire for juice and connect the other wire to the fuse box or somewhere.

Thank all you guy/gals for your help & patience.

[Fishhead]

This may or may not help. I don't know how BMW actually wired their fogs lights.

What I did on my fog installation was to run a new (power) wire to the relay from the fuse box.

Connection #9 is used as a + side feed for the relay (switch side). I didn't want my fog lights on all the time(with the headlights) so the ground (switch side of the relay) is grounded through a blower switch mounted in the fog switch spot. When the blower switch (now fogs) is pulled, the ground is completed and the fogs come on (when the switch side circuit is completed, the power from the new wire from the fuse box is allowed to pass through the relay and to the fogs) . With out the switch pulled, nothing happens.

I would use a separate relay for the fogs.

Here's a crude schematic of what I have. This wiring schematic would have Driving lights on with the high beam and Fog lights with the low beams (when the "blower switch is pulled out to 1st position- fogs, 2nd position - driving lights). Separate relays were use for both sets of lights.

The #9 connector would connect to the blue wire labeled "High Beam" . I made a connector in the low beams (similar to #9) for the power to the switched part of the relay for the low beam switch.

[penth2o]

Thanks Fish.

I'm trying to use the original setup BMW has in the harness.

If I can't get that done I will leave it the way my brother in law set it up as it ain't broke so don't fix it as they say. I will replace all wires & relays when the restore comes but I would like to get rid of all the modified methods & do it the way BMW did it.

[Jerzy]

Go here -

http://2002tii.org/kb/tag/electical-diagram

Download their 2002 Lighting Overview PDF. I think you will be able to print out a usable copy. Note that the Lighting Overview schematic does not show the horn relay. (They also have the '74tii schematic PDF you asked about in a post below)

When the fogs are on, the brights should be off - that's why there's an interconnection of the two circuits.

I'm short on time right now. Nice car, by the way. I enjoy the winter driving photos you've posted.