Hello everybody,
as much as I would have liked to proceed quicker, but as you see it has taken quite some time until my fog lights have been successfully installed. As promised in pt. 1 - switch https://forums.jag-lovers.com/t/sii-fog-lights-installation-pt-1-switch/370366 this part will continue with the wiring.
The good thing is that SII cars already have the switch and the wiring installed which makes installation of fog lights a quite simple thing - if you keep it simple, at least.
- Original setup for UK and Euro spec models:
#6 is the light switch, ## 54, 55 are the fog lights.
The fog lights are wired red/yellow from fuse #1 in the underscuttle fuse box. There is no extra relay for the fog lights nor any further fuses.
There are female receptacles for Lucas bullet connectors at the right and the left front wing that can be used directly. The ground is provided by ground brackets in the same neighbourhood at the vertical frame around the radiator.
Left side:
Ground bracket (with main beam ground wires rusted away - got to fix that
- Fog light set up permitting use of fog lights with low beam
In the UK and in Germany (that’s what I can oversee) SII cars with factory fog lights would cut off the low beam head lights and leave on only the parking (aka pilot) lights. This is not so common today, and probably for good reasons as nights with heavy fog are rare and under most conditions low beam head lights will not produce glare.
So I made up a wiring scheme allowing for use of fog lights together with low beam head lights. After some trial and error I found a wiring scheme that seems pretty much identical to the one that came with factory aftermarket Bosch fog lights in the US for SIII and XJS cars - thanks again, Mark Lee, for letting me have a copy (in fact I was unable to understand their scheme, but as soon as my system worked I understood their way of depicting …).
Only one simple ice cube relay, some feet of wire and a few “v” shaped female spade connectors are required and no cutting or even changing of the original wiring is necessary.
The use of the relay actually is a bit misleading. As you see the fog lights are fed directly from the red/yellow wire and fuse #1. The relay is only used to supply the low beam head lights with power while the fog lights are on. The original light switch will cut power supply to pin 56 at the head light relay 231 once fog lights are turned off.
That’s why the power circuit of the relay makes use of the permanent power supply at pin 81a of the head light relay (if you can’t read the wiring scheme on the housing any more: that’s where the brown wire comes in) and leads it to pin 30. Power is then led from pin 87 of the fog light relay to pin 56b of the head light relay.
Power from the fog lights is used at the control circuit (pin 85 of the fog light relay) and then simply grounded from pin 86 of the fog light relay.
As for the fabrication I wanted to keep everything as stock as possible and wanted to be able to just throw out everything without any changes. So I put the fog light relay right next to the head light relay and was able to use two very short wires (approx. 4 inches with “v”-shaped connectors allowing me to just pull the brown wire from pin 81a and the blue/red wire from pin 56b of the head light relay, push my wires on the spades and then the original wires back on the extra spade. I fabricated all the wires before and tagged them to know once and be able to identify later.
Finally, both fog lights got wired from pin 85 of the fog light relay. Because space was limited and there was already a v-connector on pin 85 I undid a part of the insulation of the wire running to the left light, soldered the wire from the right light on and covered it up with shrink tube.
Now everything is in place:
(to be continued)
Jochen
75 XJ6L 4.2 auto (UK spec)