Conversion from Sealed Beam to H4s and H1s

[Mike J]

Does any one have a definitive wiring diagram for this conversion. Have new Outer lamps with H4 bulbs with red yellow and blue off the connector. How do I wire this into the existing . Should I just use the dip feed on the H4 (whatever this is) and leave the H1s as main beam. Mike

[tjk]

HI
I did this conversion and just used the connector wiring to connect with original wiring less the high beam. Cant reminder which colour wire was which but easy to trace.

Tim

[blue 464]

Mike, i did this over the winter, used h4 bulbs on dip and main and the inner h1 on main so you get 4 main beams. good improvement in light output!. I have a wiring diagram of how i did it but cannot get on a scanner at present to send it to you. you may wish to consider an additional fuse box and relays as the main beam load is greater.
if I can get on a scanner i will post it later. the 3 wire h4 connector is wired oddly if I remember correctly, one of the side wires is the earth, not the middle as you might expect.
Derek

[malc4d]

If you look under LHD with heater (or A/c) wiring diagrams in the ROM you will see how its wired from the factory for quad lighting. Not sure if the columm switch is wired and different in RHD LHD guise though.

[Mike Stevens]

The column dip switch is different for the UK H1/H1 setup as opposed to the H1/H4 setup. Basically, the H1/H1 setup doesn't have a switched dip beam connection, only the main beam one. However, the column switch is basically the same as from Mk2 saloons, with the proviso that you swap 2 wires over in the plug. This is what I did to my Stag when I fitted the H1/H4 setup. It avoids the use of another relay, (although light output will be improved if a pair of relays is used!)

I have some photos of the Stag and saloon dip switch plugs, but I can't find them on the PC here at work!

Cheers,
Mike.

[pagan]

Only thing I can think of is..
If you're going to use 2 (inside and outside) headlamps for high beam (mains) then make sure they are going through a relay.
As the main light switch might have power problems.

[tonyh]

This may help.

The Standard headlamps fitted to UK spec Stags have single filament bulbs, H1, in both main and dip beam units, dip beam stays on when main beam is selected, to fit double filament bulbs, H4, for the outer dip units, giving four main beam lamps. Relay must be installed each side to turn off the dip beam bulbs when the main beam is selected.


One relay is used each side.

1. Connect terminal 85 of relay to a good earth.

2. Disconnect the dip beam live (blue/red) wire. Connect the wire from the dip beam lamp to terminal 87A of the relay.

3. Connect the dip beam live supply from the loom to terminal 30/51 of the relay.

4. Make up and connect new wire from the new main beam on the outer headlamp and connect to terminal 87 of the relay.

5. Connect terminal 86 of the relay to the main beam live (blue/white) using a scotchlock or similar.


Bulb connections.

Looking at the back of the H4 bulb, the top blade is the dip beam terminal, the right hand blade is the main beam terminal and the left hand blade is the earth terminal.

[malc4d]

I must ask though....Why don't the LHD cars need the relays but the UK cars do. Are you missing a couple of wires in the loom ?

[Mike J]

Brilliant thank you all. tony h, do I need One relay for each pair or will one do both. Sorry I can do spannering, but electricity is witch craft to me. Mike

[tonyh]

Two five pin 30amp changeover relays, you need one relay per side, the relay turn off the dip lamp and turns on the main beam when main beam is selected.

Tony.

[blue 464]

you can keep the dip beam on and have 4 main beams if you want MIke. pm me an email address and I will scan my wiring diagram and email it to you, Derek

[StagJonno]

you can keep the dip beam on and have 4 main beams if you want MIke. pm me an email address and I will scan my wiring diagram and email it to you, Derek

I'd be concerned about overheating if both dip and main beam in the same bulb were on at the same time. Have you noticed any such adverse effects, Derek, or am I just being a wet Nellie?

Jonno

[blue 464]

Jonno, I have not had a problem so far although they do get hotter than the h1 singles. To be honest with so much traffic around here its unusual to be able to keep main beam on for very long. I am either following something or its oncoming.
Derek

[Lingen]

Jonno. I think you are right to be concerned. With both filaments operating, the life of the bulb will be greatly reduced, and will generate a lot of heat. I think it would probably overload the contacts on the dipswitch as well, which would be expensive. With four main beams, (H4 bulbs), a relay system should really be fitted for safety.
Mike.

[blue 464]

i agree with the need to fit relays, i did, and also separate fuses on a 6 fuse board for each, Derek