1. This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.

overheating Headunit

Discussion in 'In-Car Entertainment' started by Jay, Apr 8, 2010.

  1. Jay
    Offline

    Jay Member

    Joined:
    Aug 27, 2006
    Messages:
    322
    Likes Received:
    0
    [Apr 8, 2010]
    I almost burned my hand while removing my Alpine HU. Is it normal for the metal block at the back of the HU to get so hot?
    Is there a problem with the connections of the ISO block that could cause this?
    #1
  2. AndyMac
    Offline

    AndyMac Moderator Staff Member Moderator

    Joined:
    Jun 10, 2003
    Messages:
    9,833
    Likes Received:
    35
    [Apr 8, 2010]
    That's the heatsink, it's job is to dissipate the heat generated. If you are running all speakers from the HU and listening loud then it can get quite hot as they pack in too much power in such a small space. Bear in mind the equivalent Alpine amp (same power) would be twice the size of the HU, plus you have very little airflow behind the dash. I think they have thermal cutouts if it does overheat so nothing to worry about, however if you are driving the stock system then very little of the internal Alpine amp should be being used, just the fronts and with Bose none of the HU amp should be being used unless you are using the crappy speaker input adapter.
    #2
  3. Jay
    Offline

    Jay Member

    Joined:
    Aug 27, 2006
    Messages:
    322
    Likes Received:
    0
    [Apr 9, 2010]
    Right thanks for that. I'm running the fronts and rears of the HU so thats probably it.
    The factory HU had an earth cable connected but I haven't connected this to the Alpine. Is it important that I do? Can't really find anywhere to clip the brown connector to.
    #3
  4. AndyMac
    Offline

    AndyMac Moderator Staff Member Moderator

    Joined:
    Jun 10, 2003
    Messages:
    9,833
    Likes Received:
    35
    [Apr 9, 2010]
    No the HU is already earthed via the black ISO plug, the additional Audi earth is unnecessary unless you are getting alternator whine.
    #4
  5. AndyMac
    Offline

    AndyMac Moderator Staff Member Moderator

    Joined:
    Jun 10, 2003
    Messages:
    9,833
    Likes Received:
    35
    [Apr 9, 2010]
    What type of speakers are you driving from the HU?
    If they are stock Bose then you will fry the Alpine's internal amp as the Bose speakers are 2ohm impedance, which will be why it's getting so hot.
    #5
  6. Jay
    Offline

    Jay Member

    Joined:
    Aug 27, 2006
    Messages:
    322
    Likes Received:
    0
    [Apr 9, 2010]
    i've replaced the fronts with rainbows and the rears are factory fitted
    #6
  7. AndyMac
    Offline

    AndyMac Moderator Staff Member Moderator

    Joined:
    Jun 10, 2003
    Messages:
    9,833
    Likes Received:
    35
    [Apr 9, 2010]
    Factory fit what? Bose or non Bose?
    #7
  8. Jay
    Offline

    Jay Member

    Joined:
    Aug 27, 2006
    Messages:
    322
    Likes Received:
    0
    [Apr 9, 2010]
    i've no idea. its a facelift model A3 2000 plate so unsure what they're fitted with. Pretty sure the fronts were some non branded **** so i presume the rears are the same.
    #8

Share This Page