[. . . ] When doing so, please observe the vehicle manufacturer's safety instructions. [. . . ] When doing so, please observe the vehicle manufacturer's safety instructions. - Make sure you do not damage vehicle components when drilling any holes. - The cross sections of the positive and negative cables must not be less than 1. When installing an amplifier or changer, you must first connect the device earth connections before connecting the plugs for the line-in or line-out jacks. Speaker out RR+ Speaker out RRSpeaker out RF+ Speaker out RFSpeaker out LF+ Speaker out LFSpeaker out LR+ Speaker out LR- This information is subject to change without notice! [. . . ] When installing an amplifier or changer, you must first connect the device earth connections before connecting the plugs for the line-in or line-out jacks. [. . . ]