The first check is to see that the power cord connection and docking power supply is firm and the docking station is getting power. Next see that the portable has been properly inserted into the docking station or port replicator.
Incase any device connected to the docking station does not work then bypass the docking station/replicator and try to operate the peripheral directly with the portable unit. Verify the power supply for both the docking station and the peripheral device and verify that both are turned on. Reboot the portable while it is attached to the docking station. Then check the signal cables between the docking station and the peripheral.
