No power to cb
first thing is to make sure the power leads to your CB are hooked up. The black wire from the back of your CB need to go directly to the car battery "minus" "-" or to a metal screw which is actually touching metal not plastic. The red wire needs to go through a fuse. Sometimes there are inline fuses, that is to say built into the red wire that you can remove and check. If not the the red wire should go to a wire that is coming from your cars electrical fuse box. Using a multimeter to check voltages, set it to read DC and to be able to read at least 20 volts. attach the black lead of your meter to the same screw or point where the black wire from your CB is at. Next if your red CB wire has an inline fuse remove it. we will test it in a minute. Now where you have removed the fuse, with the fuse out touch the red lead of your meter to the red wire of your CB but the half that goes the opposite direction of your CB. Is there 12 volts there? oops turn on your ignition and test again. you should have 12 volt reading on your meter, or close to that. If so that means you have power up to the fuse. Turn your ignition switch back off. Now set the meter to read ohms or if you have a buzzer symbol, set it to that. Now touch the red and black leads of your meter together, note what happens. something should happen, meter goes to almost zero and probably makes a tone, if you have it set for buzzer. Now touch the leads to the fuse while it is laying on a table. One lead to one side the other lead to the other side. Doesn't matter which lead goes where. You should see or hear the same thing you just did a second ago. If so then the fuse is good. Put it back in the red wire where it belongs. make sure both ends are snug when you fit it in and tighten up.Try your radio again with the ignition on. does it work? It should if what I said checks out. If not then you will need someone to look at your radio internally for a bad solder joint where the red wire comes in or even a bad switch. If you have made the check I suggest and you don't see anything on the meter when you check for voltage. set the meter for DC voltage, touch the leads up to your car battery just to see if the setting is right on your meter and it does work. If it does then continue on. You will need to do this: touch the red wire of your meter to your cars battery "+". You might need a longer wire to attach to the red lead to be able to reach the battery, because I want you to touch the black lead to the black CB wire at the point where it hooks to your car. Do you see 12 volts now? If not the black wire connection where it makes contact with the screw is not really grounded. Find another ground and try it again until it works. If that all checks out and the radio still doesn't work we are in trouble. The basis of this is that the red wire has to end up making a connection to the car battery "+" one way or another and the black lead of your radio needs to go to the car Battery "-". If your red wire has an inline fuse you could just run the wire directly to your battery "+" and the black wire to your battery "-" It will work if the fuse is good and your radio works. If not then your radio needs help. The drawback of running the wires like that are , would be the radio would not go off and on with the ignition switch. woopie!
Dec 12, 2010 |
Cobra 18 WX ST II 40-Channels Base CB...