H4 Bulb Socket - wiring question

[NathanR]

Hi all,

I'm starting into my H4 headlight conversion project on my 87 Carrera and am trying to figure out which wires connect to which leads on the H4 bulb socket.

The socket is configured like this:

__
I I

Does anyone know which port is the Hi, Lo and ground, respectively?

thanks
Nathan

[Nine9six]

Nathan,
Have you tried the search function?

[NathanR]

I've read about a hundred posts on h4 conversions, even seen some photos of the sockets. No one ever seemed to addressed this particular question. The photos even seem to be contradictory.

[don911]

I'd be interested in your old H5 sockets.

[NathanR]

I'll probably sell the headlights too.

[KTL]

I drew a diagram when I did mine- added relays and heavier gauge wire from the fuse panel along with the light change. I got the wiring diagram from the Bentley manual. Check that if you've got one. This is one area of the Bentley that's actually pretty reliable.

I'll look for my notes when I get home and post anything I find.

[Steve 82SC]

The brown wire is the ground on each of your H5 connectors. The rest of it should match up fairly easily if you just look at the corresponding wire(s). Once you have the ground connected, the only thing that you can do wrong is to have the brights on by pulling on the headlight knob and have them turn off when you pull the high-beam stalk. Twist the wires together and check prior to soldering. The worst case scenario is simply switching the two wires in order to have the proper function. While you're in there, do the headlight relay upgrade.

Steve

[NathanR]

Thanks Steve and Kevin.

Kevin, any notes you can send my way would be helpful.

Steve, If I get you right, you are saying the H4 socket is organize similar to the H5?

The H5 socket looks like this, if you are looking at the end:

__Y(Lo)
__ __
Bl(hi) Br(Grnd)

I wanted to wire up the H4 plugs (with solder) prior to installing the headlights. I could do this by trial and error but would rather get it right the first time if possible.

I am installing a relay kit and heavier gauge wiring.

Thanks again,

Nathan

[NathanR]

Bump

[Steve 82SC]

Nathan,

I PM'ed you

Steve

[imcarthur]

This is the Hella Heavy Duty H4 socket sold by Daniel Stern.

Ian

[NathanR]

Ian,

I also found this photo of an install in an early 80s SC.




An this is consistent with your diagram as well.

OBTW, I just bought a socket from Mr Stern, and it is a little different style -- white ceramic terminal block with black rubber boot. Very sturdy in construction, I'm quite pleased with it.

Thanks everyone!

cheers,
Nathan

[imcarthur]

fwiw here is my (overkill) wiring diagram. It works well. The snap of the relays is very satisfying. I use the city lights as drls.



Ian

[billybek]

Just about to do upgrade the lights on the SC.
Found this thread that will either confirm or confuse the issue!
Headlight pinout question

[imcarthur]

And the bucket:



All 12 AWG wiring was used after the relays. I fed 3 X 12 AWG cables, the existing 3 conductors for turn signal lamps & parking lights (yeah, I fed the small ground back too) AND another 18 AWG wire for the City Light in a bundle to the bucket. I taped them for the pass-thru area & re-used the rubber bell-shaped grommets.

Ian

[billybek]

That is a great wiring diagram, Ian. I am bookmarking this one..
What lamps are required for the city lights. I like the idea of using them for running lights.
Do you have a picture of how you mounted your relays?
Thanks

[imcarthur]

The city light is a 4W bulb that comes prefitted with the H4 kits from our host. You just have to get an 'always on' wire to them.

Here is a mess of links to older Pelican posts on the subject: H4 Upgrade Buried in these links you can find wiring diagrams for 2 relay systems also.

Here is my writeup: H4 Conversion

Ian

[billybek]

Thanks!