Question about Infinity Reference 1211a Car Audio Amplifier

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Protect light flashing/ticking

I had my Infinity 1211a mono amp hooked up to my 2.1 fared cap and 2 Infinity 12" subs and the amp worked for about a week untill it gave out and the protect light started flashing off and on and making a ticking noise while flashing unrhythmically... I left it all hooked up and occasionally the subs would kick on for a couple seconds right when my vehicle was started up but would die after that. Now the subs don't even kick on at all - not even for a couple seconds - but the protect light continues to flash. HELP PLEASE!!

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  • Anonymous Nov 05, 2007

    i have a 1868 legacy amp which everytime i turn it on i get a few seconds of sound before my protection lights cut on blocking everything

  • peyote 69 Apr 14, 2008

    i have an older jbl gtq 400 amp had a ground wire into the ground but the power light kept flashing on and off no sound another amp worked fine does this amp itself also have to be grounded to metal write me back thanks

  • Anonymous May 04, 2008

    same problem but I have the 1210a

  • Anonymous May 22, 2008

    yes I had the same problem then the amp fried so if I could all you guys that is haveing this problem with the directed 2400d unhool the ampo or you are going to fry it

  • flypaper69 Jul 07, 2008

    so, im haveing the same problem when i turn my car on with the sub attached to the amp the protect light flashes and sub rumbles, if i disconnect the subs, the light comes off, my subs are wired corectly to check i tested on two sets.

  • Brazilx2k Feb 16, 2009

    Mine protect light is always on and the power light is flashing like aver 2 secs and subs bumps also could it be the fuse on the battery cable? mine is 500watts amp but i dont need much power..



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Check your capacitor carefully(and connections),check your 30A fuses,u should have 4 guage wiring,if not that, pull your subs out the box, check the terminal wiring because they like to burn up before the voice coils.The coating will burn and crumble then the Small copper wire will burn up.

Posted on Aug 09, 2008


Transistors blown, change it

Posted on May 24, 2007

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I had a similar problem happen to my friends car...he had a visonik amplifier with 2 12" infinity....he had the same ticking noise and the prtect light flashing on and off....i first of all changed all the fuses...then checked the subs...and they were both blown...the ticking stopped when i unhooked the subs...try that and find out if they are blown...hope this helps...

Posted on Feb 27, 2007

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Yes make sure your powers and grounds are all ok. If you have round glass fuse in the power wire replace it even it it looks good. Ive seen those fuses melt the solder internally so they will be "blown" but look as if they ar eperfect.... if that does not help your amp needs repaired. go to my website at for more info. I may be able to repair it fo ryou or buy it form you as-is...

Posted on Nov 27, 2006

  • Mike Ryan
    Mike Ryan Sep 08, 2007

    hey heres some other things i should mention...
    Your ground wire and connection to the car body is just as important if not more important thasn the power wire!!! The ground wire should idealy be bolted somethere metal with a nice strong bolt. Use sandpaper or some other method to get the metal where the wire will bolt CLEAN BARE METAL!! SOme people dont realize that they use cheap krap wire. You cane use walmart 8 gauge wire to run a big stereo!!! I reccomend 4 gauge or larger quality wire, quality fuse holders,etc. I reccomend using either a circuit breaker or large blade type fuse for the power wire as the round glass fuses tend to melt internally so thry will look great but not conduct electricity at all..

    also one last thing DO NOT mount your amp on your speaker box. Not only does it make a thieves job easier, the vibration is VERY BAD for the sensitive components that are inside your amp...

  • Mike Ryan
    Mike Ryan Sep 08, 2007

    NO this amp was fine!!!! he had a problem with the power fuse... the solder in the ends of the fuse melted... it looked fine, but would barely conduct power causing ther amp to come on then abruptly cut off...I always reccomend large power wire and either a circuit breaker or blade type fuse for this exact reason..

    Yes most of the time when i amp goes into protect its either some shorted subs or just a fried amp but in this case the fuse fixed it.


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This problem sound like you have too low of power going to your amp, test your battery and make sure its putting out enough power for at least the mininum amount of power that your amp requires, you can find that information in your manual or sometimes they post it on the amp itself. i hope this info helps

Posted on Oct 09, 2006

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Just hooked up mtx 500d mono amp and 12 inch sub worked for a 1/2 hour then sub quite and led on top of amp just flashes.

either ur ohm load is way off ur pos n neg might be touchin or more than likely u blew u sub is it scratchy when u push in the middle of the cone ? does it push in at all?

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Just hooked up mtx 500d mono amp and 12 inch sub worked for a 1/2 hour then sub quite and led on top of amp just flashes.

Your amp went in to power protect. You must adjust the settings on amp. This is usually very time consuming to get it right. Good Luck

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