Time for a new daughter, ... Ahh, ... I mean radio! The first thing to consider is there are multiple fuses for the radio because the engineers have built the Body Computer into it so people cannot replace it with an aftermarket radio. One of the functions the radio does now is to provide the "click" sound for the turn signals. Since the CD player is working, we know the audio section is okay. If you do not hear the turn signal click, suspect another blown fuse. Unfortunately the fuses relate to so many things, they are not labeled for simple circuits anymore. They are labeled for computers, so it is better to just check each fuse under the hood and inside the car.
Every spade-type fuse has two tiny holes on top to provide test points. Use a test light to test for voltage at each test point. Turn the ignition switch on, then probe each fuse. If you find 12 volts on both test points, that fuse is good. If you find zero volts on both points, that circuit is turned off and is not related to the problem. You are looking for any fuse that has 12 volts on one test point and 0 volts on the other one. Don't worry about the larger cartridge fuses. Those are checked visually, but they protect numerous circuits that already have their own individual fuses. If a cartridge fuse is blown, you will have a lot more problems than just the radio.
The next thing to consider is if an antenna connector was left unplugged. Unlike home radios, car radios require a very good antenna for them to pick up stations. In rare instances it might pick up a very strong local FM station with no antenna, but on AM, you should hear the characteristic loud buzz from the interference caused by power lines. If you hear that buzz, the AM section should be working. The FM always feeds its signal into the second half of the AM section, so if the AM is not working, you wont get FM reception either. If you only hear light, steady static with the volume turned up high on AM, that part has an internal problem.
There should be multiple antenna plugs for your radio. One is for the standard AM / FM antenna, and another one is for the OnStar system, and yet another one if the radio is equipped for satellite radio. I don't know if the new antenna plug style is standardized like they were up through the 1980's, but at least one design I have worked on had a very thin wire in the center of the radio's jack, and it is real easy for that to get bent over if care is not taken when connecting that plug. Look closely at that jack to see if that wire is bent over. You might need a magnifying glass for that. If the wire is bent or broken off, you can expect to not receive any stations, and that AM buzz I mentioned will be weak or non-existent.
The radio I worked on for the broken pin was damaged in a crash. I tried to swipe the antenna connector from a different radio, but due to the design, I had it badly damaged before I ever got it fully-removed. Instead, I manufactured a wire that the antenna could be plugged into, and somehow it worked fine.
Problems in the AM and FM sections caused by coins are not common because those circuits run at very low power. There is not much to become damaged by a short circuit. I do not know what was involved in getting the coins out, but some radios have face plates and other circuit boards that plug into each other with rows of pins that are very susceptible to damage when putting them back together. It is real easy for one pin to miss its hole and get bent over. I will never admit that I have done that on at least a dozen occasions. Most of the time the fix is just to take everything apart again, straighten the pin, and put it back together.
Thinking about it, my vote for best suspect is the pin bent over in the antenna connector. After that, my guess is you will need to have the radio repaired. Unfortunately, that is going to be a dealer-only item. They have radio service manuals and parts all locked up so almost all repairs must be done by one of their two authorized service centers. Typically they will just send the dealer a different radio, then the dealer has to program it to your car. Also, the Body Computer in the radio is the master computer that tells all the other computers on the car when to wake up, so some of those may need to be reprogrammed too.
Friday, October 14th, 2016 AT 4:44 PM