[. . . ] · Be sure to install a protective fuse in the power cord near the battery. The protective fuse should be the same capacity as the unit's fuse capacity or somewhat larger. [. . . ] · Install this unit in a location which allows heat to easily dissipate. · The surface temperature of the amplifier will become hot during use. Install the amplifier in a place where people, resins, and other substances that are sensitive to heat will not come into contact with it. · This unit has cooling fan to decrease the internal temperature. Do not mount the unit in a place where the cooling fan and ducts of the unit are blocked. Blocking these openings will inhibit the cooling of the internal temperature and result in malfunction. · When making a hole under a seat, inside the trunk, or somewhere else in the vehicle, check that there is nothing hazardous on the opposite side such as a gasoline tank, brake pipe, or wiring harness, and be careful not to cause scratches or other damage. · Do not install near the dashboard, rear tray, or air bag safety parts. · The installation to the vehicle should securely fasten the unit to a place in which it will not obstruct driving. If the unit comes off due to a shock and hits a person or safety part, it may cause injury or an accident. · After installing the unit, check to make sure that electrical equipment such as the brake lamps, turn signal lamps and windshield wipers operate normally. Installation board, etc. (thickness : 15 mm or more) Protection function The protection function is activated in the following situations: This unit is equipped with a protection function for protecting this unit and your speakers from various accidents or problems that can occur. When the protection function is triggered, the Power indicator goes OFF and the amplifier stops operating. · When the unit malfunctions and a DC signal is sent to the speaker output. [. . . ] (The sound is distorted. ) The speakers wire are connected with wrong 9 / · polarity. Connect them properly checking the 9 / · of the terminals and wires well. [. . . ]