The dimming is all automatic with the wiring looms/modules that are supplied with the kit. It's literally 3 wires to connect for each light. You get two lots of what is shown in the next pic, one for each light:
black wire : connect to ground (ended up fastening to chassis ground (blue nut in right of next picture)
white wire : trigger to 'dim' - connect to pin10 on back of headlight connector (circled in next picture)
red wire : connect to switched live (12v ignition) - connected to spare switched live in fusebox in dash
Darren ended up making it into a single loom by simply fastening the two reds, two whites, and two blacks together. The reds were then extended with a single wire to go through the bulkhead behind the battery, ending up through the dash to the fusebox. So, one connection at fusebox, one ground connection and one connection to pin10 on headlight connector. The two dimming units were then passed down behind the nearside headlight, down behind the foglight. The nearside dimmer module and connector were then ready to plug in to the nearside fog/DRL light unit. The offside dimmer module and connector were passed behind the front grill/numberplate to the offside foglight area, ready for plugging in.
The DRLs are therefore fully automatic. Basically, when the ignition is on, the DRLS are on. When sidelights or headlights are on, the DRLs automatically dim to the level shown in the pics. Therefore there is no need for any coding at all.
Cheers again Darren! It's just the way I'd have connected it myself! Please correct anything I've just said!
