How to turn on fog lights for the is300 without the headlights

Why? if you dont need headlights on you dont need fog lights on.

In most places its illegal to travel with fog lights on unless they are needed and you ca be booked.

Without modifying your lighting system, you can not operate the fog lights without the low beam lights on.

You can not. You can only turn on the fog lights if the low beams are on. there is no other way. Plus, your low beams should be Xenon (HID), which have the blue glow. They are much much better than the fog lights.

You can not with the factory wiring because the headlights need to be on for the fog lights to be on. You would need to rewire the lighting harness so that the fog light switch is independent of the headlights, thus turning them on/off individually.

it can be done. l have done it. you need to access the fog light fuse/ module in the passager side kick plate (where the fuses are). you need to jump the power prong from that fuse to a fuse that is on with the ignition (an accessory fuse).