LiveFromNY

Trying to figure out the best way to wire up my euro driving/fogs. I know - "here we go again" - trust me, I did a lot of searches before I posted.

Read lots of posts with good advice, My situation is a little complicated as I've already done the Rennbay headlight upgrade.

In the end, I just want my driving lights to turn on when I activate my highbeams. I don't want an extra switch on the dash.

When we did the Rennbay headlight upgrade, we utilized the driver side headlight harness to to wire it up. The kit inlcudes two relays which are activated by the existing passenger side harness, the relays are wired directly to the alternator. So, in the end, only the driver side of the headlight harness is utilized. The passenger side of the headlight harness is not connected to anything.

I'm thinking about wiring my euro lights so that the fogs run off the existing fog light wiring, and I connect BOTH of the driving lights to the non-utlized, high-beam wires from the existing passenger side headlight harness.

I know that there is an independent fuse for the passenger side, high beams and I may have to upgrade that fuse from 7.5 to 15.

In the end the I'll be running two euro driving lights through wiring that used to run one high beam light. Are the two driving lights going to draw excessive current compared to the old single high beam and possibly cause problems?

As an alternative I could wire in a relay (maybe 40amp?), use the old headlight wire to activate the relay and get power directly from the alternator. Kind of seems like overkill as my completely uneducated guess is that the stock wirig that used to run a single headlight will be OK to power two driving lights.

JohnKoaWood

Dude, tap a new relay trigger into the existing high beam relay, run 8AWG from the battery to the relay, and from the relay to the euro fog lights... you will be able to blink them with the lights off by triggering the high beams, just as the stock fog lights turn on!

You can also tap into the wiring harness at the control stalk, but for your car it will be much cleaner to have all the relays together, tucked out of the way!

The old stock wiring will be pushed if you are running 100W bulbs that come with the euro light kits... just trust me, and run dedicated lines for the euro fogs, triggered off the high beams.

LiveFromNY

Thanks, John. I hear you. Any advice on the size of the relay?

dillon410021

I just wired mine to a separate switch which was easy

JohnKoaWood

Well, the 100W bulbs shouldn't pull more than 9A each (8.33333 by the math).. I used a 50A relay, with 15A fuses on the leads to the bulbs after the relay.. a short in the wiring, or a shorted bulb will blow the fuse before damaging the relay or battery... didn't want to use 10A fuses, nor a smaller (25A relay) as this close sizing to the maximum of the circuit tends to lead to problems in my experience... I can get some pictures if you like of my routing of the wires, but I imagine you want to keep it all as discrete as possible.. and my setup as installed is anything but...

Like I said my setup is overkill, but worked without a hitch for more than a year..

And will one day soon ride again...

odurandina

op. love your avatar. something sublime about a car up on blocks.

P. Ortiz

[QUOTE=JohnKoaWood;8215239]Dude, tap a new relay trigger into the existing high beam relay, run 8AWG from the battery to the relay, and from the relay to the euro fog lights... you will be able to blink them with the lights off by triggering the high beams, just as the stock fog lights turn on!

With this setup, can you operate the driving lights continuously even when the headlights are down? This is one reason that I'm considering a dedicated switch. My reasoning is that while perhaps not ideal, the car already has a flash to pass function built-in. A separate switch for the driving lights would give me the complete control over when I want the driving lights on or off. That said; I'm open to any ideas. My head is about to explode over this simple decision.

Voith

Is there a law anywhere in usa, that lights should be on all day? In eu almost everywhere lights must be on all the time, so usually everybody here opt for seperate switch that allows driving with lights without lights poped up.

P. Ortiz

We use daytime running lights, but not of the same intensity as the driving lights on the 951. That's why I kind of like the idea of using them or not, depending on whether there is other traffic or if I'm alone on a dark road.

JohnKoaWood

Wire it up to the switched power from the ignition and you could have the driving lights on without any other lights on... its all how you wire it to the power source for the relay.

I have mine wired to the driving lights, so the fogs and euro fogs can be on when only the parking lights are on...

P. Ortiz

Got it. Thanks.