EPIC

Ive got a 2002 is300, i just tried to replace my cluster with 2 diferent ones, and for some reason my rpm gauge dosent work, nor do the backlights work(on both). all the "christmas tree" lights work(check engine, door open, tire preasure, etc) but cant figure out why rpm dosent move and backlights dont turn on. the dimmer control works, all the lights in the dash like AC/Heater etc work. Someone know what the problem might be???