[. . . ] To prevent a short circuit, remove the key from the ignition and disconnect the - battery. [. . . ] €¢ Connect the speaker wires correctly to the terminals to which they correspond. The unit may be damaged or fail to work if you share the - wires or ground them to any metal part in the car. €¢ When only two speakers are being connected to the system, connect the connectors either to both the front output terminals or to both the rear output terminals (do not mix front and rear). For example, if you connect the + connector of the left speaker to a front output terminal, do not connect the - connector to a rear output terminal. €¢ After the unit is installed, check whether the brake lamps, blinkers, wipers, etc. €¢ Mount the unit so that the mounting angle is 30° or less. €¢ This unit has the cooling fan (page 5) to decrease the internal temperature. Do not mount the unit in a place where the cooling fan of the unit are blocked. [. . . ] After the system acquires satellites for the first time, it will acquire satellites quickly each time thereafter. [. . . ]