Thank you,
I made a video for this specific check, watch it here,
For English only videos https://www.youtube.com/results?search_query=idle+speed+control+valve
Most of old Pajero Mini have this same problem and mechanics keep misguiding people as they also don't know how to fix it.
My elder brother made clone ICs which control ISC valve,
You will have to replace ISC valve which I pointed in my video shared above, and these ICs in ECU if they are burned.