I bought a new 2006 Silverado about a week ago, and went to install a CB in it. I was planning on running the power from the radio harness. I used a multimeter to check the voltage on two of the lines in the radio harness (The orange and red ones that aren't next to any others).
After checking the lines with my multimeter, the radio now only works intermittently. It will come on just fine some times, other times it will stay in the off position, like the truck is turned off. When it's in the off position, I can press the "Recall" button, and it will display the time. Some times the radio will come on after a few minutes, other times it doesn't come on at all. Also, when that started happening, my cigarette lighter quit working. The accesory plug right next to it still works though. The only thing I did was check the voltage of those two lines...
Did you need to remove the radio in order to conduct your electrical tests and if so, were you able to put the radio back without doing any noticeable damage to the dashboard or the radio?
Did you do any damage to the wiring harness?
If your unfortunate experiment created no visible damage, take the truck back to the dealer and demonstrate your problems with the radio. Don't say anything about your attempt to hook up a CB. Hopefully, your bumper to bumper warranty will cover the problem.
The electrical components in late model Chevrolet/GMC trucks, are extremely sensitive to voltage fluctuations and the connectors are made of very cheap and flimsy materials. Dealerships are unwilling to modify a vehicle because doing so might cause problems, such as the ones that you are experiencing.
I have a 2004 Silverado work truck which comes from the factory without a cruise control. The only difference between my truck and one with a cruise control is that the vehicle with the cruise control has a different turn signal stalk and its computer is set with the cruise control mode turned on. My dealer refuses to do a cruise control upgrade to my truck because there would be no warranty on the cruise control and its installation might cause other problems. Fortunately, after driving my truck for two years, there have been very few times when I actually could have benefited from having a cruise control.
In view of the problem that you have already had, you will probably be better off if you connect your CB directly to the battery.
There is slight damage to the constant power line, since I knew it was a constant 12 volt, I went ahead and tapped a power line for the CB to it. I'm trying to figure out a way to "repair" the insulation on the wire, so it would hopefully not be noticed. I wonder if I could find some of that rubber coating in a close match to the color of the wire insulation? It wouldn't take much to hide it easily.
There are several places in the box under the dash that you can get power from which are on their own fuse so you don't have to mess with tapping any other wires. The best way to repair would be to pull the pin out of the radio plug and slide on some heat shrink tubing but it wouldn't hide anything as the repair would be noticeable, but if you do fix it then no one will ever know anyway.
Thats quite possible. My 04 would blow the SIR fuse and the display on the mirror would go out. I would replace the fuse and a few days later it would blow again. I found that the wire going up to the mirror was being rubbed by the parking brake. unplugged it and stuck my hand way up in the dash and rerouted it through the dash instead of around the bottom by the parking brake, after fixing it of course.
I just re-read your original post and noticed the part about the cigarette lighter not working in addition to the radio. The lighter may have blown a fuse. If I remember correctly, a cigarette lighter creates a short across the heating element between the positive and negative poles and a thermostat-spring pushes the lighter out when the element gets hot. (I experienced this effect the hard way after carrying a 9-volt battery in my pocket. A coin crossed the two poles and got hotter and hotter until it burned my leg.) Anyway, it could be that the cigarette lighter circuit got zapped when you tapped into the constant 12 volt line.
I'm guessing that there was enough of a surge in the electrical system to cause damage to some part of the radio circuit. Which leads me back to your statement: "After checking the lines with my multi-meter, the radio now only works intermittently." I'm not sure what method you used to check the lines. Did you need to puncture the insulation of a wiring harness in order to insert the multi-meter probes? If this was the case, it could be that two or more wires were exposed enough to touch each other.
The fact that your radio still works -- although intermittently -- indicates that there is some problem with its power supply, either with the radio itself, or the circuitry supplying power to the radio. I don't know if the radio uses one of the many Delphi relay cubes found in the under-hood electrical circuit box. If it does use a relay, this relay may have been damaged by an electrical surge.
The Delco radio/CD player in my 2004 Silverado is mated to the truck through some sort of internal scan that the computer performs. According to the dealer, if my radio is stolen, it will not work in another vehicle without being re-programming by a dealer. Maybe your radio has lost its factory-supplied code and needs to be re-programmed.
You asked for ideas, so I am just putting out a few ideas in the hope that somebody will be able to put the puzzle together.
I had a chance to look at it some more last night.
The lighter fuse was blown, so that fixed the lighter.
As far as the radio, it seems that one of the pins in the harness is loose. As I pull the radio out of the dash, it will come on, when I push it back in, it will go off. I played around with the harness a bit last night, and was able to get it to stay on when I put it back in. That worked until I hit a bump this morning, which must have jolted the pin loose again, and turned the radio back off.
I think I'll take it in to the dealer tomorrow, and see what they do with it.
Does your radio say "RDS" on it? The new chevy's incorporate some of the data systems into the radio. You may have tapped into the power of one of the control modules snd fried it through that.
There is points on the fuse block for acc's like cb's and other radios, ie scanners, and hams, thats where I always go for power when needed, and some of the points are switched with the ignition switch. check the vehicles owners handbook for the fuse block diagram, hope this helps
Was going to say the New Chevys use a Class 2 Databus to everything, including the Radio, and taping into the wires for the Radio will cause you problems! Not a good thing to do. You Need to tap into the Fuse Box to something safe. Better yet, run a Power cable directly from the Battery for the CB! Make sure there is a fuse.
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