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  1. #1

    Default Electrical Problem?

    I have a 2007 Chevy Avalanche. I have had my subs on it since a got about a year ago used. But now when my the bass drops my lights sort of flicker. The dash, interior, and tailights all do a small consistent flash when i turn up my bass. I am thinking i need a bigger alternator but I am not sure exactly what may be going on, any ideas?

  2. #2

    Default

    It is the alternator it cant handle the extreme extra draw. Buy a larger aftermarket alternator from DC Engineering or Singer alternators.

    1996 Chevy Tahoe LT 5.7L V8 4X4 205,000+ miles. Built proudly at Janesville Assembly in Janesville, Wisconsin
    Basic mods: Lights all over, bunch of electrical work, and a couple cooling mods.

    Check out my other mods in My Garage: http://www.gmtruckclub.com/forum/sho...t-Tahoe-4-Door

  3. #3

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    So with a bigger alternator i wouldnt have this problem. And why is it doing this all of a sudden now?

    - - - Updated - - -

    Thanks by the way!

  4. #4

    Default

    I'm not sure it may just be from wear and tear over time. Also as time goes on wires build up resistance therefore it takes more power to run something.

    Also I just realized I should warn you it may be a bad ground. I would check that, but if you want to add any more electrical equipment you will need more power i.e a bigger alternator.

  5. #5

    Default

    What amp output would you recommend?

  6. #6

    Default

    That I'm unsure one you need to find out how much your subs and amp draw. Most likely you have a 160 amp stock alternator. You will most likely need a 200+ amp one. Singer only makes 250 and above but they have a full lifetime warranty I mean total warranty parts, labor, everything.

  7. #7
    Jr. Engineer Jamm3r's Avatar
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    Default

    Quote Originally Posted by King_David View Post
    I have a 2007 Chevy Avalanche. I have had my subs on it since a got about a year ago used. But now when my the bass drops my lights sort of flicker. The dash, interior, and tailights all do a small consistent flash when i turn up my bass. I am thinking i need a bigger alternator but I am not sure exactly what may be going on, any ideas?
    1) It is possible that you have corroded connections either to your battery or at some other critical point. In most high power stereo installations the battery smooths out the power flow somewhat and it can't do that if the connections are corroded. So start by cleaning and tightening the connections, it's free or nearly so

    2) The internal resistance of batteries increases with age so, gradually, the battery has less and less of a voltage smoothing effect. One way to fix this is to just replace the battery. Otherwise you can increase your alternator output so that the battery doesn't have to do as much smoothing, see #4 below

    3) It is also possible that your alternator is failing. Usually when they go out it's because the diodes are going bad, and one of the six will fail first with the effect of reducing output and causing the remaining diodes to overheat and fail. If your rig works fine when you first start it up but the problem gets worse the longer you drive then this is probably what's going on -- a bad diode usually works for a little while when it's cold then goes out as it heats up.

    4) If the problem only shows up at idle and goes away when your rpms are up then you can try one of two mods to improve your alternator output at idle. Either a smaller alternator pulley, or a switch from your stock AD-230 alternator to a large-frame DR44g or AD-244 alternator. These are large frame alternators that will produce a good deal more output at idle and also somewhat more output at higher rpms. While they are made in several configurations you should be able to find one that is plug compatible though you will need a slightly longer serpentine belt.

    If you get an "overwound" alternator that is the same size as your existing AD-230 that won't help you because those produce less output at idle than the stock alternator (assuming that your stock alternator works ok). The improved output only occurs at high rpm.
    Minneapolis area - 1997 K2500 regular cab long bed + 8.5' Western Unimount plow + modified transmission + 2nd battery + modified camper charge circuit + 1971 Cayo camper -and- 2004 4x4 Suburban 2500 8.1 + Maxbrake controller + 2nd battery + modified trailer charge circuit + Reese receiver, pulls 30' Airstream trailer

  8. #8

    Default

    X2 on what @jamm3r said. But most after market alternators fix in stock brackets and use stock regulator wire. You will need to upgrade your battery to alt wire, battery grounds and add an alternator ground. Check you stock systems before shelling out 300+ for a new alt, but if you want to keep going bigger with your sound system you will need a bigger alt. A note on the Singer it has a special pulley that spins the alt faster at low RPMs so it produces 30-40 more amps then most at idle.
    DC Engineering:
    https://www.dcpowerinc.com/high-outp...engine=5.3L+V8
    Singer Alternators:
    http://singeralternators.com/

  9. #9

    Default

    Quote Originally Posted by Jamm3r View Post
    1) It is possible that you have corroded connections either to your battery or at some other critical point. In most high power stereo installations the battery smooths out the power flow somewhat and it can't do that if the connections are corroded. So start by cleaning and tightening the connections, it's free or nearly so

    2) The internal resistance of batteries increases with age so, gradually, the battery has less and less of a voltage smoothing effect. One way to fix this is to just replace the battery. Otherwise you can increase your alternator output so that the battery doesn't have to do as much smoothing, see #4 below

    3) It is also possible that your alternator is failing. Usually when they go out it's because the diodes are going bad, and one of the six will fail first with the effect of reducing output and causing the remaining diodes to overheat and fail. If your rig works fine when you first start it up but the problem gets worse the longer you drive then this is probably what's going on -- a bad diode usually works for a little while when it's cold then goes out as it heats up.

    4) If the problem only shows up at idle and goes away when your rpms are up then you can try one of two mods to improve your alternator output at idle. Either a smaller alternator pulley, or a switch from your stock AD-230 alternator to a large-frame DR44g or AD-244 alternator. These are large frame alternators that will produce a good deal more output at idle and also somewhat more output at higher rpms. While they are made in several configurations you should be able to find one that is plug compatible though you will need a slightly longer serpentine belt.

    If you get an "overwound" alternator that is the same size as your existing AD-230 that won't help you because those produce less output at idle than the stock alternator (assuming that your stock alternator works ok). The improved output only occurs at high rpm.

    I will have to try some of this out before going ahead and dropping some change on a new alt. Thanks for your help!

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