coding Fog lights?

boandlkramer

US Specs in Europe
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'17 CX-5 GT AWD; '18 BMW X3
I've modded things in the CIC using the USB file, but I'm wondering if it's possible to code the fog lights to stay on even with High beams.

anyone?
 
I don't think this can be done.

Any vehicle I have ever worked on in the past, when it comes to this mod you usually have to either short out a relay or do some sort of other wiring change so that it does not switch the fogs off when the highs go on. I am sure its the same case for out CX5's
 
I don't think this can be done.

Any vehicle I have ever worked on in the past, when it comes to this mod you usually have to either short out a relay or do some sort of other wiring change so that it does not switch the fogs off when the highs go on. I am sure its the same case for out CX5's

Agreed, not easy to mod OEM wiring, probably much easier to run a standalone system using aftermarket wire harness from battery and triggering it by splicing it into the parking lights so fogs go on when parking lights are on, or add in a switch in between parking light wire and relay harness trigger and control it by routing it to the cabin and control the fogs from there, the parking lights will automatically shut it off if you forget to turn them off.
 
I think in some areas there are laws/regulations against running fogs on high beam.
 
I think in some areas there are laws/regulations against running fogs on high beam.

I believe the original law's intent was to force compliace with an old law which restricted the number of lights (4) you could have lit on a vehicle with quad headlights.
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Could you power a relay off the high beams to operate the fogs?
 
Could you power a relay off the high beams to operate the fogs?

Yes you can with an aftermarket wire harness, you can do whatever you want , you're basically making it stand alone and decoupling it from the car's oem fog wiring circuit.

An aftermarket wire harness has a low current signal trigger wire that you hook to any powered circuit ie parking light, high beam light, low beam light, anything that you want to trigger the fogs to come on, just make sure what ever triggers it is automatically turned off when the car is off, otherwise the fogs will stay on and drain your battery.
 
So I understand, there is NO software tweak that does this?

Lame, my BMW has so much that is codeable. They're not even hacks as they are features that lawyers or bean counters felt was not necessary in the US market.

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Yes you can with an aftermarket wire harness, you can do whatever you want , you're basically making it stand alone and decoupling it from the car's oem fog wiring circuit.

An aftermarket wire harness has a low current signal trigger wire that you hook to any powered circuit ie parking light, high beam light, low beam light, anything that you want to trigger the fogs to come on, just make sure what ever triggers it is automatically turned off when the car is off, otherwise the fogs will stay on and drain your battery.

I was thinking of adding the high beam-triggered relay to the existing system, leaving the existing wiring in place.
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With the fog light's OE switch configuration, would there be a problem if the circuit was back-powered?
 
I was thinking of adding the high beam-triggered relay to the existing system, leaving the existing wiring in place.
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With the fog light's OE switch configuration, would there be a problem if the circuit was back-powered?

so I understand your intent correctly: you want to leave OEM wiring exactly as is but splice in a wire harness using the high beam wiring as a trigger ?

this might be possible but kinda risky, not sure what that will do to the electrical system,

you're basically suggesting adding a parallel circuit to the OEM one, you still need to connect the wire harness relay the to battery and splice into the + and - of each fog to the wire harness and splice in the high beam to trigger the relay.

Honestly, I don't see the value in that, you still need to have the low beam headlights on to have the foglights on if you're keeping the OEM circuit,

you're better off de-coupling the foglights completely from your OEM wiring completely and protect your OEM wiring and use the aftermarket wire harness,

The harness is nothing more than a direct connection to your battery to provide power to the fogs with a relay (mechanical switch) in between the lights and battery that is triggered by any power source. if you want to control them even more add a on/off switch in between the trigger and harness and mount the switch to driver cabin.

have the harness trigger wire connect to parking lights and then the foglights can be ON independently of the headlights and still be on with high beams, in other words, the fogs are no longer controlled by the car,

they are controlled by the aftermarket wire harness relay and you choose what you want to trigger it , be it parking lights, low beam lights, high beam lights, or you can add a switch and break the trigger circuit so you can control it whenever you want.

I suggested the parking lights as a safety measure in case you forget to turn off your lights the parking lights will shutoff after a minute when car is turned off, and that will trigger the relay to turn off and protect your battery from draining.

here's a good diagram of an aftermarket wire harness, the trigger is what you choose to turn it lights on or off

http://i140.photobucket.com/albums/r18/crazycow2/Odyssey%20Fog%20How%20To/tn_FoglightWiringLayout.jpg
 
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so I understand your intent correctly: you want to leave OEM wiring exactly as is but splice in a wire harness using the high beam wiring as a trigger ?

this might be possible but kinda risky, not sure what that will do to the electrical system...

That was my question.
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Scenario 1: assuming the OE foglights are powered by a relay that's triggered by the OE switch on the T/S stalk.
If, during high beam operation, you turn on the fog lights with another relay that's triggered by the high beam circuit, the OE relay would be supplied 12v to the relay's output terminal and go no further. The same thing would happen to the aftermarket relay during low beam fog light operation. During 'flash to pass' mode both relays would be 'back powered'.
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Scenario 2: same as above but without an OE fog light relay. The current for the fog lights passes through the fog light switch on the T/S stalk. Seems unlikely...
The 12v would be supplied to the output of the fog light switch during high beam fog light operation and to the output terminal of the aftermarket relay during low beam fog light operation.
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Scenario 3: assumes there's a CanBus in the picture.
I wouldn't go there. We'd be much smarter to isolate the fogs from the OE circuit as you suggested. In an ideal situation, you might be able to use the output of the OE switch to trigger the aftermarket relay...
Any thoughts?
 
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