Power down the TiVo and detach the power cable from the rear of the unit.
Remove the five T10 screws from the rear of the case using the Torx screwdriver.
Lift up and pull back the outer casing towards the rear of the unit.
The fan is held in by four T15 screws on the rear of the device.
Take the wound red and black wires coming from the fan and follow them back to the logic board.
Unplug the connector from the motherboard.
Pull the fan towards the front and out of the TiVo unit.