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Trouble with car audio

  1. Sep 16, 2009 #1
    Hi, my car audio keeps going on and off, on a weekly basis. Meaning for one week, it would play perfectly and for another week it would not function properly at all, in a sinosoidal fashion. I don't want to spend and buy a new radio, but is there anything I can do to break this pattern without consulting a professional , speaking as a non-expert on fixing car audios?
     
  2. jcsd
  3. Sep 16, 2009 #2
    So when it's not working you get audio distortion or no sound?
     
  4. Sep 16, 2009 #3
    just no sound. The audio completely shuts down.
     
  5. Sep 16, 2009 #4

    DaveC426913

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    Sounds like bad wiring.
     
  6. Sep 16, 2009 #5
    Most likely - unless my 16 year old son and his friends have been helping.:rolleyes:
     
  7. Sep 16, 2009 #6
    Do you work one week in the mountains and then one week in the city?

    Just asking :rolleyes:
     
  8. Sep 16, 2009 #7
    you think I could fix it by myself?
     
  9. Sep 16, 2009 #8

    BobG

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    Before it broke, did the volume vary depending on the engine RPM? On some cars, the volume automatically lowers when the engine is idling at a stop light and then rises as you accelerate (the acceleration would be expected to give louder engine noise, hence the volume increasing).

    If the volume automatically raises and lowers, the wiring is slightly more complicated and will be a little tougher to troubleshoot on your own.

    Either way, intermittent problems are the pits. Hopefully, the bad wiring will eventually result in a short circuit, some blown fuses, and possibly some other fried components (hopefully, not too many in the car's ignition circuitry). The damage from the short will be easier to detect than the intermittent problems.

    (This sounds silly, but putting up with intermittent problems until a part finally broke down completely was just part of the package in controlling satellites, where the ground system could be complex enough that the maintenance guys just weren't going to be able to pinpoint intermittent problems.)

    And, unfortunately, taking it to a professional tech may not do you that much good if the problems are intermittent. It's one of the variations of Murphy's Law that intermittent problems always disappear whenever a qualified maintenance technician looks that the system.

    I still remember how difficult it was to recreate the problem I had with the headlights on my Corvair. They never shut off unexpectedly while sitting in the mechanic's lot in the middle of the day. The only way to recreate the problem was to drive down the interstate in the dark, where the lights would shut off and turn on almost randomly (well, bumps in the road had something to do with it, but the bumps came along pretty randomly.)
     
    Last edited: Sep 16, 2009
  10. Sep 16, 2009 #9

    The volume gradually did no lower, it instantly shut off. For a while, I had a method for reviving my car radio; I would bang on it and instantly would come back on. Now when I try to bang on it with my fix, it does not work and so I will have to wait another week .
     
  11. Sep 16, 2009 #10

    BobG

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    I guess the symptoms could still give you some clue, even if intermittent. The power stays on (the lights stay lit), but the volume drops? Does the volume drop just for radio, or does it drop for radios and CDs? Does the volume drop for each speaker? (This is the problem with intermittent problems - this part might be tough to figure out. Ideally, when the volume is out, check each speaker. The reduced volume could be because you've lost one or more speakers vs the volume itself dropping.

    The symptoms should give you some clue as to which wire is causing the problem. With no clues, you're pretty much going to have to reconnect each and every wire coming from your stereo, tightly, plus check to make sure none of the wires are broken or have the cover worn off (the latter is what would give you a short, potentially causing lots of problems). It's better to check one or two wires thoroughly than blow through the problem because you're sick of checking wires by time you happened to check the problem wire.

    You should really call Car Talk about this problem. They helped me with my brake problem a couple years ago: http://xkcd.com/582/
     
    Last edited: Sep 16, 2009
  12. Sep 16, 2009 #11

    DaveC426913

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    It could just as easily be internal to the component.
     
  13. Sep 16, 2009 #12

    DaveC426913

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    Assuming you are careful to not make it worse, there is no harm in trying to locate the problem yourself. Be systematic.
     
  14. Oct 5, 2009 #13

    Ouabache

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    It depends on how handy you are working with hardware (dissassembling part of your dashboard to pull out your radio, interpreting the wiring at the rear). The systematic part, I believe Dave is referring to, are things like testing each speaker (via its appropriate wires), using a suitable reference (a working audio source), running the signal for each output channel to a test speaker.
     
  15. Oct 5, 2009 #14
    you think I should obtain an extra external audio source? How would that help me fix my radio?
     
  16. Oct 6, 2009 #15

    Ouabache

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    That's just part of a systematic procedure. You may test each output channel of your stereo into test speakers first. If that works, you will know that your car stereo is okay and you won't need the external audio source. However if it fails, you can use an external audio source to verify the stereo is the source of the problem and also to verify that your speakers and associated wiring, are okay or not.
     
  17. Dec 15, 2009 #16
    Sure, if you like backbreaking work of laying on your back and staring into the innards beneath your dash!

    Seriously - some people do just this, pulling every coupling and either hard-soldering it, or using better connections that what existed.

    I'd do it, but then again, I sort of like doing this. If you don't, save your aggravation and simply buy a new head unit for $250 and tell them you want all new wiring...
     
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