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Tips
Tips

BJ8 headlight relay

Dealsgap

Freshman Member
Offline
I have a 1965 BJ8 with high beams and fog/driving lights all wired to the dash light switch, and predictable short switch life. I'm thinking of putting a relay between the switch and all headlights. Anyone done this before and have a schematic?
 
Hans, does the aux light switch between the dip switch and driving lights relay serve any purpose other than convieniently turning off the driving lights?
 
Dealsgap,

In many states, you can only have your driving lights on with your high beams. This is a good thing as the wide light from your high beams compliments the narrow distant light from your driving lamps. The auxiliary switch is present for the times when you would like your high beams and not the driving lights. An example of this condition happened this evening when I was driving at reasonably slow speed near home on the lookout for deer crossing the road. I needed the extra bright wide lights of the high beams but not the narrow distant light of the driving lights.

If you would like your driving lights completely separated from your head lights, connect the auxiliary switch to the light switch. Additionally, if you would like your driving lights always on with your high beams, you can either tie the trigger connection of the relay directly to the dip switch high beam circuit or eliminate the driving light relay and connect your driving lamps directly to the high beam lamp circuit.

Good luck,
Ray (64BJ8P1)
 
Thanks Ray, I love your site and its information

Hans
 
Hans,

I appreciate the kind words and, although I am as site contributor, I will forward them to John Sims, the site's owner, creator, and maintainer. He lives close by and is in the same club.

A couple of decades back, I spent quite a bit of time in Eindhoven and Best with Philips.

All the best,
Ray (64BJ8P1)
 
I highly reccomend installing the relays. I used one for low beams and another for high beams. I first measured the voltage at the headlights and found I only had about 10V DC after routed through the original type light switch on the dash. By diverting the 12V DC supply through the relays I had about 11.5 VDC and the lights were noticably brighter. When wired the original dash switch is only used to operate the relays, then the relay contacts have their own, fused, battery supply. I bought relays, pre-wired relay holders and fuses through "Parts Express" for about $15 plus postage. The relays I ordered have auxiliary contacts and with the pre-wired holders I can add even more accesories later if I wish.

I have more info if you need it, send me a PM with your email address.
 
One last point. However you choose to wire your relays, you will have the capacity to use much higher powered head lamps. However, let me caution you that the wiring to your original headlight plugs is very low gauge and potential to failure. Although some have installed Halogens without issue, I would not be surprised if the light produced is under-capacity due to this wiring choke. I would suggest you consider creating a new harness from the relays to the headlight plugs capable of delivering the full power capacity of your new relay-based circuits. You will have the choice of continuing to use ā€˜50/’60 technology with headlight wattage of 30-40W/40-50W or moving up to 2K technology using 7ā€ sealed beams at 60W/100W of power. If you choose the later, you will need to upgrade the pipe delivering the power to the lamps to enjoy the full performance.

Ray (64BJ8P1)
 
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