2001 Jeep Cherokee raidator fan

Welcome to the forum. Do you know what is wrong with the fan? If the fan motor is faulty, it won't run, no matter how you hook it up. Take the fan connector loose, use jumper wires to the battery posts for B+ and ground, use an inline fuse. If the fan won't run, the motor is faulty. Next, I'd check the voltage circuits to the fan relay. Voltage to the load side of relay is hot all the time. Voltage to the coil side of relay goes hot when you turn on the key. The coolant temp sensor can also have an effect on fan operation.