BMW radios can suffer from a variety of problems, whether its a non-functioning radio, a jammed CD or a code error. This can be more common on older models, many of which came with Alpine stereos from the factory. The display can grow dim, and some of the functions, such as what radio station the radio is picking up, will not work at all. If you are willing to tackle the job yourself, there are a few fixes that can be performed with some basic tools.
If the radio is not functioning or says "code," it probably needs to have the code entered. If you do not have this code, BMW sells the code for as much as $65. Before entering the code, disconnect the battery to reset the radio, then follow BMW's procedure for entering the code. Sometimes problems with newer radios arise when aftermarket components like iPods and navigation systems are installed. If the radio does not function, these components may need to be removed.
If there is a problem with the volume suddenly going up or down when the controls are used, spray some electronic cleaner on the control's contacts to remove any dust and dirt. This often fixes the problem.
Jammed CD messages on the head unit are sometimes associated with trunk-mounted CD changers. First, disconnect the wires to the unit to reset it. If this does not work, the CD changer must be repaired or replaced. If there are strange noises coming from the speakers, they are either blown or have a bad connection to the back of the speaker. This may require re-soldering the connections. Remove the speakers to inspect the connections. Soldering is not that difficult and often fixes the problem.
The radios on older BMWs often have lighting issues where the display is dim or not functioning. To properly fix this, the radio needs to be removed. Open the hinged tabs that cover the bolts and use a small wrench to unbolt the radio. Remove the plastic cover and then pull off the top cover, usually held on with two screws. Remove the display circuit board and then the tape or CD player. This should reveal the main board. Check the bulbs to see if they are getting power. If they are not, they are burnt out. Replacing them is a little complicated but possible for a home mechanic.
