Eonon Optical Fiber Decoder Box Designed for E90A12S,Q65SE,Q65PRO Car Radio, Compatible with BMW E90/E91/E92/E93-A0581

?Installation Steps?1. Take the black plug out of the decoder box, and remove the plastic protective cover from the plug. 2. Connect the factory car fiber optic interface to the black plug, and then reinsert the plug to decoder box. 3. Connect the decoder’s ACC, GND and BATT cables to the same cables of your car. And connect the White & Red RCA interfaces to the audio output interfaces of car stereo. 5. Installation completed. ?Please confirm with us before purchg?If your original car has Logic 7 system, or the original car interface has fiber optic and no 8 speaker cables, you need to buy A0581 fiber optic decoder box to install. If the original car has fiber optic interface and 8 speaker wires, combined installation (A0581 fiber optic decoder box is not needed).