Right then. I’ve been following old recommendations from the PCGB forum on how to cancel the silly ‘dim-dip’ action that 944s from the late eighties have. I’m having trouble getting it to work though, and nobody over there seems able to help figure out why.
Here’s the goal: See how the main headlights pop up when you switch on your sidelights? I want to stop that happening. It was a short-lived legal requirement at the end of the eighties, and it’s not necessary at all now.
Here’s the instructions that seem to work for most people:
Quote:
1) Remove 'relay' G6, this is not actually a relay but a series of links.
2) Remove the plug from the dim-dip unit. This will be found above the accelerator pedal (right hand drive car) and is a silver box roughly cigarette packet sized. The plug will have wires of the following colours, Black/yellow, White, Yellow, Brown, and Grey.
3) Tape up the removed plug and tuck it away in the loom. The contacts whilst shrouded will be live when light are on, so we want to take no chances.
4) Make up 4 link wires from 1.5mm wire approx. 8 cm end to end including crimps. Put a male spade type crimp (lucar) on each end.
5) Connect the sockets you removed G6 from as follows,
0 - 4
9 - 2
5 - 7
6 - 8
2) Remove the plug from the dim-dip unit. This will be found above the accelerator pedal (right hand drive car) and is a silver box roughly cigarette packet sized. The plug will have wires of the following colours, Black/yellow, White, Yellow, Brown, and Grey.
3) Tape up the removed plug and tuck it away in the loom. The contacts whilst shrouded will be live when light are on, so we want to take no chances.
4) Make up 4 link wires from 1.5mm wire approx. 8 cm end to end including crimps. Put a male spade type crimp (lucar) on each end.
5) Connect the sockets you removed G6 from as follows,
0 - 4
9 - 2
5 - 7
6 - 8
And here’s a picture of the successful modification on someone else’s car:
Attachment:
hlmod.jpg [ 127.96 KiB | Viewed 18309 times ]
Now, I’ve followed the above instructions, my wiring matches the above perfectly … but it doesn’t quite work as it should.
Sure enough, switch to sidelights and they come on without lifting the headlights. Great. But, switching up to headlights, they still don’t pop up. Damn.
I checked and double-checked, I’ve removed the connection from the dim-dip unit and all my link wires are in the right places where relay G6 used to be. I’ve double-checked their positions against the photo above.
But the headlights no longer work.
Has anyone got any idea what might be going wrong? For now I’ve put everything back to normal and it’s all working just fine.
i will look at the circuit at the weekend as i'd like to do this mod..( i've done mod's to disconnect dim/dip circuits on 80's Ford's,,note no headlamp motors to operate)..... but as Jim says this is quite a complicated circuit, i can almost sense a diode pack and latching double pole single throw relays with added double park headlamp motors to attack 
I have sidelights in my headlights. Doesn't everyone.........