• Hi Guest!
    You can help ensure that British Car Forum (BCF) continues to provide a great place to engage in the British car hobby! If you find BCF a beneficial community, please consider supporting our efforts with a subscription.
    There are some perks with a member upgrade!
    **Upgrade Now**
    (PS: Subscribers don't see this gawd-aweful banner
Tips
Tips

Power to the relay

Share this page

tahoe healey

tahoe healey

Yoda
Country flag
Offline
For those who offered suggestions re: Halegon lights for my BJ8, a big thanks. I'm taking the plung. I understand the set up for the relay but is there a need for a power source since the present system is powered. If so, where is a good place to get this power form the battery (brown wire I assume)?
Also, I'd like to keep the original wire colors (like the blue w/red and blue w/white at the dipper switch). Is there a way to get them in small quantities(don't need 500 ft)? Napa sells only basic colors (like blue).
Thanks
TH
 
Hi Rich,
If you want to use one relay, you could interrupt the blue wire in the photo at the butt connector. Use power from the brown terminal on the fuse block.
 

Attachments

  • 17139.jpg
    17139.jpg
    57 KB · Views: 219
tahoe healey said:
For those who offered suggestions re: Halegon lights for my BJ8, a big thanks. I'm taking the plung. I understand the set up for the relay but is there a need for a power source since the present system is powered. If so, where is a good place to get this power form the battery (brown wire I assume)?
Also, I'd like to keep the original wire colors (like the blue w/red and blue w/white at the dipper switch). Is there a way to get them in small quantities(don't need 500 ft)? Napa sells only basic colors (like blue).
Thanks
TH
Click to expand...

Hey Th, :savewave:

I was advised to run a new power wire and fuse that wire.
If you want to chance using the cars existing brown wire and not tap into the blue/white and blue/red wires on the firewall side, tap into all the wires under the dash.

The small length of wire needed to tap into the relays not need be the same color wire, for you can see the short trace and will be out of sight under the dash. Just use the same gauge wire for the taps. There comes a point about.. hey the wires are the wrong color.. well there should not be a relay there either; should the comment come up. But if you really want the same wire, then Greg's recommendation is spot on. Mabye BCS too.

Best of luck with your project.
Roger
 
Why tap into the wires under the dash?? a criteria that can be used here is to get all the high current circuits out of the cockpit area,--Fwiw--Keoke
 
Keoke said:
Why tap into the wires under the dash?? a criteria that can be used here is to get all the high current circuits out of the cockpit area,--Fwiw--Keoke
Click to expand...

Keoke, I think TH is trying to hide all the mods he's doing. Where do you suggest he tap and place the relays?
 
Just like Greg shows and is in keeping with my KISS modification. Actually if TH hooks into the fused side of the brown wire he can get some measure of safety too. I put the relay on the firewall in the engine compartment. See my Miss Blue's picture here on the forum I point out the relay. My jumpers are not more than s few inches long.--Keoke
 
Thanks guys. The purpose of the colored wires is not to hide anything (as pointed out, there are relays that don't belong). It is for finding fault when something goes wrong and all the wires are the same color 'cause I ain't getting any younger and the memory is the second thing to go (the back is the first so get your mind out of the gutter).
I think I should make a diagram of MY wiring for the next owner (25 years form now) as well as a record for my trouble shooting. So many project, so little time.
Again, if I am using the original wiring, is it necessary to have power from the battery to the relay? The lights get power from the blue (with red or white trace) wires and are grounded complettoing the circute. Since its source of power to the lamps is after the dipper switch, why does the relay need power? I have mentioned that I am electricly challenged.
 
:yesnod: Need power
Hi TH you want to provide the existing light circuit with the highest buss voltage available void of all the previous wiring's voltage drops. So we use the relay to ;
1] to remove the high switching current from the cockpit and light switch; Blue wire now energises the relay located in the engine bay
2] Switch a slightly higher buss voltage [ Brown wire ] on to the remaining Head light circuit. B/W or B/R.
 
There are two ways to tackle this. The simpler method would be as I explained earlier by tapping into the blue wire. The downside to this is you'll have full current running through the dimmer switch in the cockpit (might not really be an issue). If you want to keep the high current all in the engine bay, use two relays, one for the blue/white wire and one for the blue/red wire. This puts the load on the wires downstream of the dimmer switch (closer to the headlights).
 
Mo Greg I do not feel the dimmer switch poses an issue it is capable of switching the power from Boulder dam . Further. its duty cycle is very low. I feel the less wiring that has to be added along with fewer components maintains a higher reliability for the modification.--Keoke
 
I agree with ya' sir. I included the two relay way later in the spirit of full disclosure. :angel:



What was that acronym? Oh yeah, KISS!
 
In my opinion, the best way to power headlight relay(s) and any other new electrical accessories is to run a new wire off of the 12 volt terminal screw on the starter solenoid to use as the new power source. If you want to keep it simple, put a 30 amp or so automotive circuit breaker type fuse in line on this new wire to protect the new relay(s). If you want to get fancier, run this new wire to a multi position fuse block instead of the one 30 amp circuit breaker and then use one of the outputs for your headlight relay(s), another for fog/driving lights, another for any new radio or amplifier, etc.
...
This is just to provide the power source. You can choose to follow either of the previous suggestions as to where to tap in and place one or two relays for your headlights.
...
There is another good thing that happens if you power your lights with this new brown wire. It takes the majority of the current draw out of the rest of the existing lighting wires and switches. This will almost certainly keep all of the Lucas smoke securely installed in your existing wires and dash switches for the rest of the car's and your natural life time.
:jester:
Ed
 
Yes Ed that is correct if you plan to add more high powered electronics to the car . I utilised that approach in my original KISS circuit post.However, in this case the owner only wants to install new head lamps which are brighter than the original sealed beams but of the same power consumption. Therefore, a very lightly loaded Always hot circuit has been chosen to provide the switched power source.
 
tahoe healey said:
Keoke, you referred to pictures of Miss Blue on the forum. I don't know how to fine it. Can you guide me there? Just look in the fourm section"Members Pictures" Select K and then Keoke there you are.
Click to expand...

:savewave:
You also have an E-Mail.
 
Greg -

Looking at your pics, I note your throttle shaft bush is very worn. You must replace before driving your car!!

Alan
 
Hi Alan,
Thanks for noticing. I threw that bushing away and never replaced it. I have no need for it. :laugh:
 
I'm thinking to either draw power form the brown wire side of the fuse box and put a fuse in line (30 amp ok?)or draw form the green wire side which is already fused. Would I need another fuse in line there? A third choice is the brown wire at the regulator. Is 14 gauge good enough cause I have brown 14 gauge already? Any thoughts? Thanks for the help cause I am obviously weak in the electrical dept.
 
Back
Top