Fog light wiring feed from dipped beam headlight - where?

[tintinmt]

Hi. I am part way through wiring a rear fog light into my Toyota Crown Estate.

I have a kit with relay and fuse etc and I'm trying to make a neat job of it.

So far, so good, but I was expecting to be able to tap into a feed for the dipped headlights under the dash on the driver's side.

Sadly, the only wiring diagram available for the car is in Japanese so pretty useless to me - although admittedly I'm not sure I would be able the read it even if it was in English.

I thought I would be able to identify the wiring from the headlamp switch but all I found is a 12v supply that seems to go off when the switch is operated.

I have tried tracing the wiring back from the headlamp itself without success so far.

I may have to resort to an auto electrician, but I have a feeling that there will be a lot of sucking of teeth due to the lack of diagrams etc.

 

Is there a convention on where to get power for the relay? I believe that it must be live only when the dipped headlights are on.

Any thoughts on how to identify an appropriate supply?