Results 1 to 10 of 10

Thread: Electrical problems with my car?

  
  1. #1
    Status
    Offline
    john1981's Avatar
    AOC Obsessed
    Join Date
    Jan 2006
    Posts
    1,180
    Mentioned in
    0 Post(s)
    Quoted
    0 Post(s)

    Electrical problems with my car?

    Hey Guys,

    Since buying my coupe I have always had a minor electrical problem. First I noticed that when I push the button for my electric windows all my dials dim, and so do my headlights. Also when I start the car and the car is idling the headlights are dimmer than normal, as soon as I give it some rev's they brighten up.

    Since then I have added subs and amps into the boot and made the problem much worse. I have replaced the battery for a 72amp which did not resolve the problem. I have installed a power cap in the boot, but that made no difference.

    My thought is it might be the alternator! What are your guys thoughts? Should I go get a new alternator and possibly upgrade to a 120amp?

    John
    Drives: Astra MK4 Coupe 2.2 & MK4 Estate 1.7TDI (Car Modification Diary)

  2. #2
    Status
    Offline
    Autosparks's Avatar
    Technical Advisor
    Club Team
    Join Date
    May 2003
    Drives
    VXR Nurburgring
    Location
    N/W London
    Posts
    39,743
    Mentioned in
    115 Post(s)
    Quoted
    70 Post(s)
    To be honest before changing everything else I would have got the alternator checked out to see if it's charging at near 14 volts.

    It may be it's not charging fully
    Want a professional job done on fitting your aftermarket electrical accessories? PM me for a quote
    Electrical fault finding also taken on
    Located in N/W London HA3, and willing to travel within reason





  3. #3
    Status
    Offline
    john1981's Avatar
    AOC Obsessed
    Join Date
    Jan 2006
    Posts
    1,180
    Mentioned in
    0 Post(s)
    Quoted
    0 Post(s)
    Cheers, is that something I could do myself?
    Drives: Astra MK4 Coupe 2.2 & MK4 Estate 1.7TDI (Car Modification Diary)

  4. #4
    Status
    Offline
    GB's Avatar
    AOC Obsessed
    Join Date
    Jan 2006
    Location
    Leeds
    Posts
    21,918
    Mentioned in
    0 Post(s)
    Quoted
    0 Post(s)
    cross the battery terminals with a multimeter and check the voltage (if ya dont have one - get one - u can get them dirt cheap now from about 5 quid or so - digital of course)

    with the engine at idle and no accessories switched on the battery should be recording circa 14.2-14.4 volts.

    anything below about 13.5 and above 14.8 give or take - would suggest the alt is under/over charging.,,, remember over charging is just as bad if not worse as it'll fry ur battery.

    Could be a quick fix with a replacement voltage regulator - cheap enough to replace... Could be a new unit - again cheap enough if u know where to look.

    First of all ascertain alternator output then take it from there.



    Personally I'd but it down to the alt not bein upto the job - big battery & big ICE together with standard 100A alt really aint the best combo.
    Let us know how u get on anyway

  5. #5
    Status
    Offline
    john1981's Avatar
    AOC Obsessed
    Join Date
    Jan 2006
    Posts
    1,180
    Mentioned in
    0 Post(s)
    Quoted
    0 Post(s)
    Quote Originally Posted by GeordieBandit
    cross the battery terminals with a multimeter and check the voltage (if ya dont have one - get one - u can get them dirt cheap now from about 5 quid or so - digital of course)

    with the engine at idle and no accessories switched on the battery should be recording circa 14.2-14.4 volts.

    anything below about 13.5 and above 14.8 give or take - would suggest the alt is under/over charging.,,, remember over charging is just as bad if not worse as it'll fry ur battery.

    Could be a quick fix with a replacement voltage regulator - cheap enough to replace... Could be a new unit - again cheap enough if u know where to look.

    First of all ascertain alternator output then take it from there.



    Personally I'd but it down to the alt not bein upto the job - big battery & big ICE together with standard 100A alt really aint the best combo.
    Let us know how u get on anyway
    LOL I just got an multimeter on the battery and when the engine is running with nothing turned on in the car its running between 13.98v and 14.04v which I assume is normal.

    I noticed today when the indicators are on the headlights and dials on the dashboard dim also.
    Drives: Astra MK4 Coupe 2.2 & MK4 Estate 1.7TDI (Car Modification Diary)

  6. #6
    Status
    Offline
    john1981's Avatar
    AOC Obsessed
    Join Date
    Jan 2006
    Posts
    1,180
    Mentioned in
    0 Post(s)
    Quoted
    0 Post(s)
    BTTT

    Anyone any thoughts?
    Drives: Astra MK4 Coupe 2.2 & MK4 Estate 1.7TDI (Car Modification Diary)

  7. #7
    Status
    Offline
    Autosparks's Avatar
    Technical Advisor
    Club Team
    Join Date
    May 2003
    Drives
    VXR Nurburgring
    Location
    N/W London
    Posts
    39,743
    Mentioned in
    115 Post(s)
    Quoted
    70 Post(s)
    My car does everything yours does and has no problems
    Want a professional job done on fitting your aftermarket electrical accessories? PM me for a quote
    Electrical fault finding also taken on
    Located in N/W London HA3, and willing to travel within reason





  8. #8
    Status
    Offline
    Ffoeg's Avatar
    2170:01:06
    Join Date
    Jun 2003
    Posts
    34,591
    Mentioned in
    2 Post(s)
    Quoted
    0 Post(s)
    do they brighten up if you blip the throttle?

  9. #9
    Status
    Offline
    john1981's Avatar
    AOC Obsessed
    Join Date
    Jan 2006
    Posts
    1,180
    Mentioned in
    0 Post(s)
    Quoted
    0 Post(s)
    Quote Originally Posted by Ffoeg
    do they brighten up if you blip the throttle?
    Yes, when I push my foot slightly on the throttle the lights brighten up. However if I am driving along and I push the windows up even though they are at the top, all the dashboard lights dim and the headlights. It also sometimes does the same when I put the indicators on, but normally only when the car is idling.

    This problem was happening before I connected up my sub etc, so it should not be anything I have done that has caused it. Although when the sub is on even when driving the lights really dim with the bass.
    Drives: Astra MK4 Coupe 2.2 & MK4 Estate 1.7TDI (Car Modification Diary)

  10. #10
    Status
    Offline
    john1981's Avatar
    AOC Obsessed
    Join Date
    Jan 2006
    Posts
    1,180
    Mentioned in
    0 Post(s)
    Quoted
    0 Post(s)
    I am still having this problem and I am no where nearer to solving it. Could it be that I don't have a good enough earth? Do I need a better alternator?
    Drives: Astra MK4 Coupe 2.2 & MK4 Estate 1.7TDI (Car Modification Diary)

Similar Threads

  1. Mk5 electrical problems
    By kevtwad in forum Astra Discussion & Chat
    Replies: 1
    Last Post: 17-09-2011, 16:55
  2. Help!, Electrical problems
    By matt_mph in forum Electrical
    Replies: 2
    Last Post: 18-04-2006, 18:18

Posting Permissions

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