My warm idle is 800 RPM and my idle-up is about 900-1,000 RPM. I was flabbergasted by it at first too when I bought my Tracker (a '90 w/ 1600 8v) because I was unfamiliar with it. It idles up when I turn on the parking lights (and headlights too) and any heater/AC fan. All my offroad lights don't activate it, though, so I figured it must be wired only into those select few circuits
I've never looked at the Tracker wiring, but on a Suzuki there's a diode assembly that is wired to specific circuits to form what is known as "wired OR gate", that controls the "idle-up". Depending on the particular vehicle, I've seen the following circuits wired to it ...
1) - side or park lights
2) - blower fan
3) - rear screen defrost (if ftitted)
4) - electric radiator fan (if fitted)
5) - a/c compressor (if fitted)
6) - power steeting pump (if fitted)
It may seem strange that the side/park lights are catered for, but none of the other lights - however, with the standard wiring, the side/park lights turn on before the headlights and/or any factory fitted auxuliary lights, so if your off-road lights don't activate it, I would suspect they were added later and do not use the side/park light wiring as a control source.
I believe this type of circuit is common on most current vehicles, I've been seeing it on Japanese cars for the past twenty years or so.
