Headlight wiring mystery

[ukbiggles]

Hi all

I have been given a new set of standard headlights (from the Bros) as an early Xmas pressie, and am fitting them today. On the outer lamps, the wiring deliverd by the main loom has only two wires - one black and one blue/red. Interestingly, the existing wiring uses the blue/red wire differently. Given that there are 3 connections on the bulb, and if the black is 1 , the adjacent middle pin is 2 and the final pin is 3, the nearside lamp is wired with blue/red to pin 2 , and the offside is wired to pin 3!!

The replacement mini harness delivered with the new lamps has three colours (black, blue/red and blue/slate?)

I presume that if the main wiring loom has only two wires then I need to connect the correct pin on the bulb to the blue/red of the loom.

So which pin of the bulb is the dip filament? If it's pin 2 , then I'm assuming it must be blue/reds together. But is that right?

Should I have three wires on the main loom, so that the main beam filament of these bulbs can also be used. Or would that be a modification?

As usual, thanks in advance for your help.

Cheers

Gord

[milothedog]

Hi all

I have been given a new set of standard headlights (from the Bros) as an early Xmas pressie, and am fitting them today. On the outer lamps, the wiring deliverd by the main loom has only two wires - one black and one blue/red. Interestingly, the existing wiring uses the blue/red wire differently. Given that there are 3 connections on the bulb, and if the black is 1 , the adjacent middle pin is 2 and the final pin is 3, the nearside lamp is wired with blue/red to pin 2 , and the offside is wired to pin 3!!

The replacement mini harness delivered with the new lamps has three colours (black, blue/red and blue/slate?)

I presume that if the main wiring loom has only two wires then I need to connect the correct pin on the bulb to the blue/red of the loom.

So which pin of the bulb is the dip filament? If it's pin 2 , then I'm assuming it must be blue/reds together. But is that right?

Should I have three wires on the main loom, so that the main beam filament of these bulbs can also be used. Or would that be a modification?

As usual, thanks in advance for your help.

Cheers

Gord

H4_Pinout.jpg

Any use, If you want to use both beams you will need to install a relay with another supply.

Ian.

[V Mad]

Your loom is designed only to use with the original single filament lamps (H1 bilbs). One wire is the live feed, the other is ground return. The new lamps you have must be fitted with twin filament (H4) bulbs, which Ian has shown the connections for. You will have to decide whether you want to use just one filament as is or both filaments and add the extra wiring necessary.

[ukbiggles]

Ian, Chris, many thanks for your help. I'll wire the low beam then, as I don't use the car much in the dark. Maybe add the high beam later , if I ever get to move from 'essential' to 'nice to have' jobs!!

Cheers

Gord