Closed Thread
Results 1 to 8 of 8

Reload Thread: Installed a New HU why are volts reading 12v on guage?

  1. #1
    APitBullT's Avatar
    APitBullT is offline Senior VIP Member



    Join Date
    Dec 2003
    Location
    Scottsdale, AZ
    Age
    30
    Posts
    218
    Post Thanks / Like
    Mentioned
    0 Post(s)

    Installed a New HU why are volts reading 12v on guage?

    I just installed a new HU my buddy gave me, and the volt guage reads 12v when i reverse. but when i rev the engine in drive it goes back up. was my battery drained when i installed the deck?

    also im hearing a low humming noise when the volume is at 0, and its very annoying, i checked the rca's but nothing is wrong there. what could this noise be?



    1 RF T30001BD
    4 12" JL Audio 12W6V2-D4
    CDT HD-62 Comps.
    Optima Red Top 75/35 (Front)
    260 Amp Alternator
    Deep Cycle Yellow Top
    1/0 AWG Knukonceptz Wiring
    "Big 3" Upgrade




  2. #2
    djjdnap's Avatar
    djjdnap is offline FreakyFreaks ofall Freaks



    Join Date
    Mar 2002
    Location
    indy-nap-lis
    Posts
    1,971
    Post Thanks / Like
    Images
    2
    Mentioned
    0 Post(s)

    Re: Installed a New HU why are volts reading 12v on guage?

    when in doubt check your ground(for the noise)
    Also, about the 12v, not sure y it would read that, when you start your car it should charge back up, especially if you have a 260alt. Just let the car run for a while it should charge back up. or let autozone charge it for you.i think its free?



    KArAudio.COM


    OMGROFLHI2ULOLLERZTITSHAHAHAHASEALEDMTWTFSTFUKTHXB YENO0B
    -Nick

  3. #3
    APitBullT's Avatar
    APitBullT is offline Senior VIP Member

    Threadstarter


    Join Date
    Dec 2003
    Location
    Scottsdale, AZ
    Age
    30
    Posts
    218
    Post Thanks / Like
    Mentioned
    0 Post(s)

    Re: Installed a New HU why are volts reading 12v on guage?

    alright thanks bro



    1 RF T30001BD
    4 12" JL Audio 12W6V2-D4
    CDT HD-62 Comps.
    Optima Red Top 75/35 (Front)
    260 Amp Alternator
    Deep Cycle Yellow Top
    1/0 AWG Knukonceptz Wiring
    "Big 3" Upgrade

  4. #4
    Chevyaudio's Avatar
    Chevyaudio is offline :poof:



    Join Date
    Mar 2005
    Location
    Back in the Dirty BR, Louisiana
    Age
    27
    Posts
    13,157
    Post Thanks / Like
    Mentioned
    0 Post(s)

    Re: Installed a New HU why are volts reading 12v on guage?

    definatly check the ground for the noise problem.




  5. #5
    APitBullT's Avatar
    APitBullT is offline Senior VIP Member

    Threadstarter


    Join Date
    Dec 2003
    Location
    Scottsdale, AZ
    Age
    30
    Posts
    218
    Post Thanks / Like
    Mentioned
    0 Post(s)

    Re: Installed a New HU why are volts reading 12v on guage?

    which ground should i check? the HU OR AMP?



    1 RF T30001BD
    4 12" JL Audio 12W6V2-D4
    CDT HD-62 Comps.
    Optima Red Top 75/35 (Front)
    260 Amp Alternator
    Deep Cycle Yellow Top
    1/0 AWG Knukonceptz Wiring
    "Big 3" Upgrade

  6. #6
    jsloan10's Avatar
    jsloan10 is offline Registered User



    Join Date
    Apr 2005
    Location
    anywhere
    Posts
    982
    Post Thanks / Like
    Mentioned
    0 Post(s)

    Re: Installed a New HU why are volts reading 12v on guage?

    High output alternators have a tendency to need greater RPMs to develop their 14volts, one option to help this is to replace the belt pulley with a smaller one to increase its rmps when the motor is at idle.
    As for the hum here is a complete guide for getting noise out of the system-


    2 Electrical
    *****************

    This section describes various problems and concepts which are closely
    related to electronics.


    2.1 My speakers make this high-pitched whine which matches the engine's
    RPMs. What is it, and how can I get rid of it? [IDB]
    ================================================== ========================

    The answer to this section was generously provided by David Navone of
    Autosound 2000. The material in these instructions was adapted from
    the Autosound 2000 Troubleshooting Flow Chart by Ian Bjorhovde with the
    permission of Autosound 2000. For more information about Autosound
    2000, (see Section 7).

    This is a set of instructions to debug a stereo installation if there
    is any noise present after it is completed. Follow each step
    carefully! If you have more than one amplifier, repeat level one for
    each amp to be sure that none of them are responsible for the noise.


    2.1.1 Level 1: Check out the Amplifier(s)
    ------------------------------------------

    After you have determined that there is noise in the system, determine
    if the amplifier is causing the noise. To do this, mute the signal at
    the inputs to the amp by using shorting plugs. If there is no noise,
    then the amp is fine, and you can proceed to level 2. However, if
    there is noise, then use a test speaker at the amp's output. If this
    stops the noise, then the problem is originating in the speaker wiring,
    or the passive crossovers. Check to make sure that none of these are
    shorting with the body of the car, and start again at level 1. If
    noise is still present when using the test speaker, then there may be a
    problem with the power supply on the amp. Try connecting an isolated
    power supply - if this does not get rid of the noise, then there is
    something seriously wrong with the amp, and it should be replaced. If
    the noise goes away, then there may be a problem with power supply
    filtering or isolation. This can be fixed by changing the amp's ground
    point or b adding external supply filtering.


    2.1.2 Level 2: Reduce the System
    ---------------------------------

    The amps have been determined to be noise free. If you have any
    processors between the head unit and the amps, disconnect them and
    connect the head unit directly to the amp. If this gets rid of the
    noise, then one (or more) of the processors must be at fault, so
    proceed to level 5. Otherwise, try running the signal cables over a
    number of different routes. If you are able to find one that does not
    produce any noise, permanently route the cables in the same manner, and
    proceed to level 5. If not, then you must isolate the head unit from
    the car's chassis (except for its ground!) - don't forget to disconnect
    the antenna, since it is also grounded to the car. If isolating
    the head unit does not solve the problem, the move the grounding point
    of the head unit. Hopefully the noise will be gone, and you can
    install the head unit with a quiet ground and proceed to level 5,
    otherwise go on to level 3.


    2.1.3 Level 3: Move the Head Unit
    ----------------------------------

    The amplifiers are fine, but moving both the ground for the head unit
    and the signal cables does not solve the noise problem. Take the unit
    completely out of the dash, and put it on either the seat or carpet,
    and run new signal cables to the input of the amp. If this solves the
    problem, re-install the head unit, one step at a time and skip to level
    5. But if the noise persists, then move the head unit as close to the
    amp as possible and use the shortest possible signal cables. This will
    verify that the original signal cables are not causing the problem -
    assuming the noise is gone, reinstall the head unit one step at a time
    and go to level 5. Otherwise, there may be a problem with the power
    filtering for the head unit. As with the amps, power the head unit
    with an isolated power supply (again making sure that the head unit
    isn't touching the car's chassis at all). If the noise goes away, you
    can add power supply filtering or an isolated power supply; go to
    level 2. But if the isolated power supply does not solve the problem,
    then you can either replace the head unit and go to level 2, or check
    the car's electrical system in level 4.


    2.1.4 Level 4: Testing the Car
    -------------------------------

    There does not seem to be a problem with either the head unit or the
    amplifier, and the car's charging system is suspect. To see if this is
    the case, we can use a system in a car that is already known to be
    "quiet." Bring both cars together as if you were going to jump one,
    and use jumper cables to connect the two batteries. Start the engine
    of the car with the noise problem, and listen to the "quiet" car's
    system. If the noise does not go away, there is a SERIOUS problem with
    your car's electrical system (possibly a bad alternator). Have a
    qualified mechanic check the charging system out. If there is no noise
    in the "quiet" car, then the "noisy" car's charging system is
    definitely quiet, so continue with level 5.


    2.1.5 Level 5: Adding Signal Processors
    -----------------------------------------

    We have proven that the amplifiers are good, the head unit is good, and
    the car's electrical system is good. Now we need to reconnect each
    signal processor. Repeat this level for each signal processor used in
    your system; if you have added all of your signal processors, and
    there is no longer any noise, CONGRATULATIONS! You've removed the
    noise from your system! Connect the signal processor. If there
    isn't any noise, then go on to the next signal processor. Otherwise,
    try re-routing the signal cables. If this cures the problem, the route
    them permanently over the quiet path, and install the next processor.
    If not, then isolate the processor from the car's chassis except for a
    single grounding point. If this works, then permanently isolate the
    processor, and move on to the next processor. If isolation does not
    help, then advance to level 6.


    2.1.6 Level 6: Processor Isolation Tests
    ------------------------------------------

    Now, noise enters the system when one particular processor is
    installed, but regrounding it does not help. Move the processor very
    close to the amp, and check for noise again. If there isn't any, then
    re-install the processor, carefully routing the cables to ensure no
    noise, and continue at level 5 with the next processor. Otherwise, use
    an isolated power supply to power the processor, making sure that no
    part of the processor is touching the car's chassis. If this solves
    the problem, the consider permanently installing an isolated power
    supply or possibly a 1:1 transformer, and go to level 5 with the next
    processor. Otherwise, separate the processor and isolated power supply
    from the car by many feet and re- test. If there is still noise, then
    there is a serious problem with the processor's design. Get a
    different processor, and continue at level 5 with it. If separating
    the power supply and processor from the car does solve the noise
    problem, then either the processor is damaged, or your tests were
    inaccurate. Repeat level 5.




  7. #7
    djjdnap's Avatar
    djjdnap is offline FreakyFreaks ofall Freaks



    Join Date
    Mar 2002
    Location
    indy-nap-lis
    Posts
    1,971
    Post Thanks / Like
    Images
    2
    Mentioned
    0 Post(s)

    Re: Installed a New HU why are volts reading 12v on guage?

    making a smaller pully for low rpms is nice, but think about when you do 80 on the highway, can you say fried system.



    KArAudio.COM


    OMGROFLHI2ULOLLERZTITSHAHAHAHASEALEDMTWTFSTFUKTHXB YENO0B
    -Nick

  8. #8
    jsloan10's Avatar
    jsloan10 is offline Registered User



    Join Date
    Apr 2005
    Location
    anywhere
    Posts
    982
    Post Thanks / Like
    Mentioned
    0 Post(s)

    Re: Installed a New HU why are volts reading 12v on guage?

    Thats why they have voltage regulator built into them..




Closed Thread

Similar Threads

  1. Best Places to buy 2 guage wire from????
    By Geminidj2000 in forum General Discussion
    Replies: 10
    Last Post: 12-12-2004, 09:35 PM
  2. HU and the SUB
    By marcopolo in forum General Discussion
    Replies: 26
    Last Post: 10-13-2004, 10:38 AM
  3. installed my new hu today...
    By Tek in forum General Discussion
    Replies: 3
    Last Post: 01-04-2003, 12:07 PM
  4. HU recommendation for a 2002 BMW M3
    By mav2002 in forum General Discussion
    Replies: 11
    Last Post: 08-12-2002, 04:20 PM

Posting Permissions

  • You may not post new threads
  • You may post replies
  • You may post attachments
  • You may edit your posts
1e2 Forum