Could anyone tell me if the rear fog lamp switch on a 2003 Disco SE can be used to connect to four Hella 500s? I don’t use the rear fog lamp at all so was wondering if it could be repurposed. If not, would a standard fog switch be a better choice? New they are about $65, used around $20. Looking for most cost effective solution.

Thanks!

 

Absolutely. You'll have to use the switch to activate a relay and then the relay will power the lights.

 

 

The front/rear fog light switch isn’t a latching switch. I’d grab a spare Cruise control switch & pigtail & then just swap the face plate. The switch needs to latch with aux wiring/relays.

 

You could use the factory module from the BCU and use that for the new lights. Cut and splice, but it would be wiser to use a latching switch as it will guarantee operation

 

Twix, yes that can be done. I used the original fog lamp harness and connectors on the newly installed non factory fog lights, but, the bulb wattage is the same and it worked fine. But the question is that the rear fog seems to have lower in wattage which I'm not sure yet but it also seems like its just a low wattage bulb not a halogen H1 type. So, ultimately if that (rear) circuit can handle higher wattage. Thanks

 

Easily. Assuming you get a 40 amp relay which is pretty standard, at 12v it's good up to 480 watts. Watts is just voltage multiplied by amperage.

I second a latching switch. You could as mentioned leg off of the power wire going to the lights, but a latching switch would be a little simpler system, so more reliable.

 

I'd be less worried about the relay, and more worried about the size of the wires from the BCU, if each bulb is 110w, that's 440w total, which would be about 37amps. You'll need a wire which is 10ga or bigger or it could melt/catch fire. This is why I recommend a latching switch so the power side of the circuit can be pulled to handle the load in question.

 

You can slap a CC switch wired into an aux 40amp light harness & then tap into the other switch illumination to make it look 100% OEM. I would not trust the OEM wiring for that many lights or amps.

 

I'm not recommending powering the lights through the BCU wiring. I'm saying you could switch the relay from the BCU wiring. The relay would draw power directly from the battery.