Join Date: Dec 2006
Location: Gloucester, Gloucestershire, England
For electronics enthusiasts
This rear fog light business...
There is an unused 21W filament in the back light assembly, but I haven't found an easy way to wire it. So I have given some thought to a way to use it without running cables. I came up with an idea about using a small control module. The signals available in the tail light are indicators, brake and tail, so how to make use of them?
It needs some combination that would not generally be used on the road that will latch the fog light on. So how about hazards running, tail light on and flick the brake light on? That could be sensed by a 4 input AND gate and fed to a thyristor relay driver. To turn it off again, switch off the tail light (that is supplying the rail voltage to the module. )
Very low cost. CMOS 4082, little thyristor, cheap relay and some wire.
Just pussin' through.