TROUBLESHOOTING14If you suspect something is wrong, immediately switch power off.Do not use the unit in abnormal condition, for example without sound, or with smoke or foulsmell, can cause fire or electric shock. Immediately stop using it and call the store where youpurchased it. Never try to repair the unit by yourself because it is dangerous to do so.General1) Car's engine switch is not on.- Turn you car's key to ACC or ON.2) Cable is not correctly connected.- Check the connection.3) Fuse is burnt.- Replace fuse.4) Volume is in mute or minimum.- Check volume or mute on/off, adjust volume to a desired level.5) The operation keys do not work.- The built-in micro computer is not working properly due to noise.Press the RESET button to restore the program to zero.Radio1) Much noise in broadcasts.- Station or signal is too weak. Select other stations of stronger signal level.2) The antenna cable is not connected.- Insert the antenna cable firmly into the antenna socket of this car radio.3) Preset station is reset.- Battery cable is not correctly connected. Connect the battery cable to the terminal that isalways live.USB1) USB is connecting but no sound- USB c onnection is not good. Take it out and insert again.- USB i s damaged or no music file inside. Change to another USB , or record music inside it.