This is a real pet peeve of of subject for me because if done incorrectly can not only compromise operation, but very dangerous. I see the question constantly here on the forum, while some advice is good, I see a lot of bad advice again and again. So lets bust some myths and get down how and why to properly terminate your power cables on all mobile radio installs. First up is the Black Negative aka Ground wire from your radio. This is the one conductor that can get you into trouble real fast, and most radio manufactures do not help and even give horrible instructions. They make it possible for you to mess up royally. You open up the box and find the DC Power Cables, unroll them, and you have two equal lengths of Red and Black wire with In-line Fuse for both Red Positive and Black Negative wires. You will even see web sites telling you how to improperly use the hardware that goes something like this: "Route both positive and negative to engine compartment and terminate both conductors to the respective polarities directly on the battery Term Post". DO NOT and I repeat DO NOT terminate the Negative Black Wire to the Battery Term post or use a fuse on the negative wire. Here is why and once you understand might slap yourself for not understanding and doing it wrong. Even worse advising others to do that. You are putting your Radio in parallel with the Bonding Straps in the engine compartment. Pop the hood and look. From the Battery negative term post you will see one, maybe two Bonding Jumper wires. One going to the Chassis, and the second a larger jumper to the engine block for the starter motor. You create a parallel path if you connect the negative directly to the negative battery term post. The path is through your black radio wire to the radio chassis of your radio and completed through the coax shield to where ever you installed the antenna like the roof or bumper. Do you know why that is a horrible practice yet? Think about it. It means a portion of everything electrical in your car is now using your radio as a conductor back to battery. Turn on the head lights, some of that current is going through your radio. You name it air conditioning, car computer, electronics, all of it. Even some of the starting engine current is going through your radio. That alone gives you operational headaches. What do you call an unwanted current or voltage? Did you say noise? That is just what you did, added a bunch a noise. You created a bad Ground Loop. There are good loops but that topic is another discussion. Even a bigger problem scenario is set up called the Dooms Day Scenario. Your local shade tree mechanic or you worked on your car and disconnected the Bonding Jumper from the battery to chassis. Now he/you goes and tries to start the engine and one of two things happen. Your radio and radio wiring emit magic smoke. Or if you are lucky the fuse you put on the Negative Conductor of your radio to the battery term post blows and saves your radio. Your radio is now the only return path for the vehicle. You have now compounded a problem in the installation making it very unsafe on top of operational issues under normal operating conditions. All this can be avoided by following best practice, electrical code, and what all auto manufactures recommend. Bond the Black Negative wire from your radio to the chassis as close as possible to the radio. Keep the wire as short as possible. Now your radio is on its own Dedicated Circuit and cannot share load current with anything else as it is no longer in Parallel. So now when your ignorant mechanic disconnects the Bonding Jumper under the hood and forgets to reconnect it, nothing happens because nothing has power. Your radio is no longer in parallel that can provide an unintended parallel path.That is a bad Ground Loop. DO NOT install a fuse on the Negative circuit some radio manufactures supply and many here on the forum advocate using. That is for ignorant people who terminate directly to the battery term post. Your vehicle electrical system is a Grounded System and thus the Grounded Circuit Conductor ( black radio wire), shall be solidly bonded with no disconnect devices inserted. All a fuse and extra wire does is add unnecessary resistance causing higher voltage losses and is DANGEROUS. You never put a switch or fuse on a grounded circuit conductor. You never want to disconnect the ground without disconnecting the battery un-grounded circuit conductor first. Otherwise you loose your protection and turn your Black Radio wire into Red Hot Conductor with full supply voltage available looking for ground. As for the Red Positive conductor is pretty simple. Take it to the battery Term Post and use an in-line fuse as close as possible to the battery. In fact they make Fuse Blocks that mount directly to the battery term post leaving no unprotected wire . That completes the Dedicated Circuit and prevents Gremlins from getting inside your radio.