11 replies to this topic

[lordyoung1980]

Has anyone converted their headlamps to run with a relay? I have a 1979 mini 1000 auto. I want to Be able to put higher powered bulbs in it. Obviously they would be too much or the standard wiring so I thought it best to use a relay circuit. I've used the halfords rally bulbs which are a higher wattage in my Frontera and the difference was like day and night,pun intended. Has any one got a mini specific diagram I can work to?

[cal844]

You can buy a plug and play kit from wired by wilson (wilson1330 on here, search his username)

Top bloke to deal with, great workmanship and also rapid delivery!

[timmy850]

If you are buying a generic relay they normally have 4 pins:

12V from battery 

Earth

Wire to switch (12V when on)

Wire to bulb/accessory

 

I've got a couple of twin relays which are useful for headlights as you then only need the one earth and power for both circuits. They are also fused for low and high beam. e.g.

https://www.mokeforu...48591#msg148591

They are a little bulky but the wiring is pretty easy, just figure out where your headlight wires are and cut them and put some terminals on as below:

B - Battery 12V on a new thick wire

S - Earth on a new thick wire

S1 - Wire to switch on low beam (or dipped beam)

S2 - Wire to switch on high beam (or main beam)

L1 - Wire to low beam bulb

L2 - Wire to high beam bulb

[paulrockliffe]

It's worth having a read about relays and how they work, then working out how to do the wiring yourself.  It's not difficult when you understand what the relay is doing and it's much better to understand it rather than just copying a wiring diagram.

 

Fundamentally the relay is a switch controlled by an electromagnet.  So you have the normal switch wiring, then you have your existing wiring switching the electromagnet on and off.  The only quirk on that is that you wouldn't normally earth the headlights via the relay, it would be earth directly to the body/battery and the relay has it's own earth, which is effectively becomes part of your existing switch circuit, with the electromagnet having replaced the headlights on the circuit.

[Carlos W]

It's also worth bearing in mind that the plug and play kit mentioned above provides a relay per filiment limiting the risk of total loss

[tiger99]

Make sure that you have seperate earths for left and right side lights, and relays, to take advantage of the safety features. A single earth for all relays would be an additional single point if total failure.

[skoughi]

I bought the same kit from Wired by Wilson, top quality bit of kit and very well assembled. A very good chap to deal with.

[WiredbyWilson]

Make sure that you have seperate earths for left and right side lights, and relays, to take advantage of the safety features. A single earth for all relays would be an additional single point if total failure.

 

Is that why the original wiring system only has one main earth point and has coped, in the main, well for 50 years?

It is the concept behind how all modern cars are wired, save they have circuit specific earthing points at the front and rear of the vehicle along with a main earthing point in the engine bay.

​Once again Tiger, IMHO, you are commenting against the norm with little justification or sound reasoning.

Edited by WiredbyWilson, 02 December 2016 - 01:53 PM.

[WiredbyWilson]

Has anyone converted their headlamps to run with a relay? I have a 1979 mini 1000 auto. I want to Be able to put higher powered bulbs in it. Obviously they would be too much or the standard wiring so I thought it best to use a relay circuit. I've used the halfords rally bulbs which are a higher wattage in my Frontera and the difference was like day and night,pun intended. Has any one got a mini specific diagram I can work to?

 

My kit is £65 built ready to plug in and takes no more than an hour to fit. Full instructions and support given via email, along with a warranty. Order now and have it by Christmas - that's a promise!

[JBW]

When I did mine, I measured 0.5 volts higher via the relays, as against the voltage drop through the switches on the original wiring, whilst mine already had a fuse for each filament, the big advantage to me was the reduced load on the switches, which should help their longevity.I know of more than one person who has had total failure due to headlight switch going open circuit.

A very worthwhile improvement. 

[WiredbyWilson]

When I did mine, I measured 0.5 volts higher via the relays, as against the voltage drop through the switches on the original wiring, whilst mine already had a fuse for each filament, the big advantage to me was the reduced load on the switches, which should help their longevity.I know of more than one person who has had total failure due to headlight switch going open circuit.

A very worthwhile improvement. 

 

I really do need to get on and do a comparison of old vs relay - may need to re-instate one side on my car to see what its like. Problem is I cant factor in butchered and bodged connections as my car hasn't been attacked like some others i've seen.

 

Christmas How To Project it seems :)

[tiger99]

 Modern cars, and the last of the real Minis most certainly do not use single point earthing as it is a major safety hazard. The headlights are ALWAYS separately earthed, as are left and right tail light clusters.