If the light is green, it’s indicating that the controller is off. The most likely problem is that the yellow ignition input isn’t getting 12V. It’s not critical without the U/D jumper, since the controller will over ride to on if it gets disconnected, but with the U/D, it will over ride to off so that it doesn’t kill the battery if the car isn’t running. The easy way to check it is to turn the AC on, it’ll over ride the ign input, but will only run the fan at 50% instead of 100%. If that’s the case, check your 12V connection to the ign and make sure that it’s good.
It sounds also that you have the regular continental fan (16” blade) If so, the or/brn is low speed, it’s not what’s causing the problem, but you’ll eventually want to change it to yel/brn (+) and blk (-)