A: If the radiator fan is not coming on when the engine temperature rises to an excessive level, the first step is to check the fan relays in the underhood fuse/relay box. If the relays are okay, the next step is to check all wiring and connections to the fan motor. If no obvious problems are found, the issue could be with the Engine Coolant Temperature (ECT) sensor or the Powertrain Control Module (PCM). In this case, it is recommended to have the radiator fan system and circuit diagnosed and repaired. To remove the fan/shroud assembly, start by disconnecting the cable from the negative battery terminal and raising the vehicle on jackstands. Drain the cooling system and remove the front stabilizer bar (for 2005 and later models). Then, remove the air filter housing and intake duel/resonator. Disconnect and plug the expansion tank hoses. Remove the radiator support mounting bolts and the radiator support itself. Make sure to correctly reassemble the tabs on the radiator support into the fan shroud slots. For 2004 and earlier models, disconnect the throttle body heater hose and the expansion tank hose on the radiator. Unscrew the transmission oil cooler line fittings from the radiator and remove the transmission cooler lines from the sides of the radiator. For 2005 and later models, disconnect the transmission oil cooler line from the radiator using a quick disconnect tool. If equipped, use pliers to remove the spring clamp on the oil cooler hose located at the bottom of the radiator and pull the hose off. Disconnect the fan harness electrical connectors and detach the wire harness clips from the fan shroud, moving the harness away from the shroud. Lift the shroud up until the tabs on the shroud are free from the radiator (for 2004 and earlier models) or remove the fan shroud-to-radiator mounting bolts (for 2005 and later models). Lift the fan/shroud assembly from the vehicle without damaging the radiator cooling fins. To detach the fan blade from the motor, remove the nut from the motor shaft and remove the fan blade. Finally, to detach the motor from the shroud, remove the retaining bolts. Installation is the reverse of removal, making sure to reconnect the battery and refill the cooling system. Start the engine and allow it to reach normal operating temperature, then check for leaks and proper operation.