Fog Light Wiring Assistance

CREEPUR

Guest
I am adding fog/driving lights and want them to go off when I switch the High Beam on (due to PA regulations). I already isolated the high beam wire and low beam wire and I have 2 relays 5-pin and a 4 pin.

Am I on the right track here.

The 4 pin relay - used to keep lights on with low beam

Terminal 30/51 connects to battery
Terminal 85 connects to ground
Terminal 86 low beam wire as the trigger
Terminal 87 output to Terminal 30/51 on the 5 pin relay

The 5 pin relay - used to shut lights off when highbeam is turned on

Terminal 30/51 connects to terminal 87 on 4 pin relay
Terminal 85 connects to ground
Terminal 86 is the high beam trigger wire
Terminal 87A connects to the Fog/driving lights - power is removed when highbeam triggers

Does this make sense or am I making it too complicated.
 
I would think you only need to use is one relay, with the relay control power (trigger) connected to the low beam power. Then connect the switching contacts of the relay that closes when the relay is energized to the fog lights and power. When you swith on the high beams, the relay would lose power, and off go the fog lights.

If you dont want the fog lights on all the time that the low beams are on, add a on/off switch in the one relay control power.

Maybe I'm missing something........
 
I thought when you switch the high beam on the low beam line is still energized since the high beam switch turns on the second light. I'll check it again.
 
Creepur, the low beam does stay on when high beam is selected. That's part of what makes a (well-aimed) NT headlight a pretty effective tool for shining light down the road.

I barely understand the simplest electrical circuit, but I think you're on target with the two relay system -- unless there might be times in places other than PA where you would want your driving lights on with the high beams.

Which lights are you installing?

I've got the original Denalis and since I got my headlight aimed right (first it was way too low, then I made it way too high; I've finally got it right), I haven't been flashed by oncoming traffic. I've got them mounted low (on the fender) and apparently they don't blind oncoming drivers. They do punch out a bit farther than my low beams and they fill in the ditches pretty well.
 
CREEPUR said:
I thought when you switch the high beam on the low beam line is still energized since the high beam switch turns on the second light.
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You're right. I was missing something....I did not know that both high and low beams are on with high beams on. Sorry bout that.
 
You should be able to do it with only one relay. Power to the fog lamps thru the NC contacts of the relay. Power to the high beams energizes the coil of the relay thus opening the contacts, turning fog lamps off
 
mikesim said:
You should be able to do it with only one relay. Power to the fog lamps thru the NC contacts of the relay. Power to the high beams energizes the coil of the relay thus opening the contacts, turning fog lamps off
Click to expand...

I am not installing a switch so wouldn't the lights stay on after I shut bike off since the +12 is coming from battery? , thought is my first relay acts as the switch.


Phil - I am looking to get Denalis or Moto lights haven't decided yet. Right now I am testing it with an inexpensive brand I picked up.
 
The 5 pin relay is what you need to turn the fog lamps off when the high beam is energized. You'll energize the 85 pin with the High beam light but run your fog lamp lights off of the 87A pin. Leave the 87 pin unused. The 87A pin will be always energized and will turn off once the relay receives power on the 85 pin (high beam light turned on). The 87 pin only gets energized when power is sent to the 85 pin (a 4 pin would work if the low beam turn OFF when the high beam went on).

5pin relay pins
86 pin to ground
85 pin to high beam line
87 pin (empty) - tape off this pin to prevent contact since when the high beam is on, this pin is energized
87A pin (feed direct to fog lamps or fog lamp 4 pin relay)
30 pin (12v power source - battery or fuse panel)

If you want to add an additional on/off light for the fog lamps then you would use your second relay on the feed off of the 5pin relay's 87A pin. The 4 pin relay would only be energized when the high beam is off. If your switch is lit, then it would only be lit when the high beam is off.

4 pin relay for fog lamp on/off switch
86 pin to ground
85 pin to fog lamp switch
87 pin to fog lamp
30 pin 87A pin from 5 pin relay

You could also put the 4 pin in front of the 5 pin if you like. You'd just have to change the 30 pin's feed accordingly.
 
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Hello,

I connected my fog light with a 4 pins relay:
85 to fog lamp swith
86 to high beam
87 fog lamps
30 to +12v.

high beam is like ground when not lighted .When you switch high beam on,there is no ground so the relay disconnects.

you can put a fuse in +12v line.
Thats the way my fog lamps are working .On with switch on and off when high beams are on.

Here ,in France,low beams are always on and there is no switch to put it off.
 
CREEPUR said:
I am not installing a switch so wouldn't the lights stay on after I shut bike off since the +12 is coming from battery? , thought is my first relay acts as the switch.

Yes, you are correct. I am sorry for "assuming" that you were going to provide a switched power source as opposed to wiring them directly to the abttery.

Mike
Click to expand...
 
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