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Dimming lights in truck

Discussion in 'Commercial Snow Removal' started by f350dieselemt, Dec 6, 2004.

  1. f350dieselemt

    f350dieselemt Member
    Messages: 89

    I just got 2 new batteries for my truck and when i raise my plow all the way,,, and then try o raise it more all my lights dim and sometimes they dim when turing it side to side.,.... does anyone know why
  2. Vaughn Schultz

    Vaughn Schultz PlowSite.com Addict
    Messages: 1,565

    Mine does that too, I bought it that way so i just always thought it was due to the extra draw of power. Never had any problems with it anyways. :rolleyes:
  3. Crumm

    Crumm Senior Member
    Messages: 529

    Because you are putting more load on your alternator than it is putting out. Your battery's are probably around 13 volts. Your alternator probably puts out about 14 volts. When you work the pump hard it is drawing more amps than your alternator is putting out so the voltage drops from 14 to 13 thus making the lights dim a little. Nothing to worry about unless you are running your battery's way down then you will need to get a bigger alternator.
  4. LINY Rob

    LINY Rob Senior Member
    Messages: 478

    its just the draw on the charging system, check all the connections to make sure they are clean and tight then learn to live with it unless you can upgrade your alternator, even then they will still dim a bit im sure
  5. f350dieselemt

    f350dieselemt Member
    Messages: 89

    Ok I Got Ya

    Ok I Understand Now I Was Just Making Sure It Was Not My Truck Messed Up.... Thanks Alot Brothers...
  6. Tarkus

    Tarkus PlowSite.com Addict
    Messages: 1,113

    When you run against the stop (lift topped out) and keep trying the pump pressure increases until relief valve comes in and when pressure increase so does power requirements to run pump and hence the additional dimming of lights.
  7. avalancheplow

    avalancheplow Senior Member
    Messages: 318

    No matter what you do they will still dim. I have tried everything, and came to the conclusion its the draw from a electric plow!
  8. Tarkus

    Tarkus PlowSite.com Addict
    Messages: 1,113

    Actually you can make it dim proof if it really bug you but it is a bit complicated and not done the way you would think either. (requires a extra circuit and relay too)
  9. f350dieselemt

    f350dieselemt Member
    Messages: 89

    its ok im leaving it

  10. nysnowman

    nysnowman Junior Member
    Messages: 22

    Tarkus i would like to know your solution,can you explain it

    CARDOCTOR PlowSite.com Addict
    Messages: 1,304

    i have the same problem with my truck i normally dont plow with my headlights on, just parking lites and strobe and never shot the truck off
    if i have to get out and shovel i leave the truck idle and give the battery
    a chance to catch up
  12. Crumm

    Crumm Senior Member
    Messages: 529

    I would also like to know. The lights are dimming because all the electrical accessories are overpowering the alternator and dragging the battery down. Only way I know of is to provide more power (bigger alternator or extra battery).
  13. mreamer

    mreamer Member
    Messages: 85

    One method for eliminating the "dimming" is to isolate the plow pump circuit from the truck electrical system. This could be done by adding an extra battery and an extra alternator, both of which would be completely dedicated for the plow. The only common would be ground (negative). I have done this before for a couple friends of mine, and it works fine. The most difficult part is finding a spot for the extra battery; the alternator we used came with a mounting bracket, which made installation a snap. In the "off" season, the battery is removed, as well as the belt used to drive the aux. alternator. Let me know if anyone would like to know more about this, or wants more details on the "dimming."
  14. DJL

    DJL Senior Member
    Messages: 343

    I'd be interested.
  15. nysnowman

    nysnowman Junior Member
    Messages: 22

    im intersted also
  16. mreamer

    mreamer Member
    Messages: 85

    (This is obviously for electric over hydraulic plow systems only). The parts needed would be (1) one wire alternator (it could be done with a standard alternator, however, the initial wiring would be considerably more complicated); (1) battery (at least the size of the existing battery in the truck); several feet of heavy wire (I would recommend at least 4 gauge), and several different terminals for the heavy wire

    After installing the new alternator, and battery (make sure the battery is secured), wire the single output terminal of the alternator to the positive post of the new battery.

    I have seen some aux. alternator kits that come with different brackets to help mounting. Most of the new trucks use a single surpintine belt, which a longer one is supplied. When the aux. alternator is not needed, just replace the belt with the original one.

    Locate the heavy wire that goes from the plow motor solenoid to the existing battery. Remove the cable from the battery, and connect it to the new battery (the alternator wire will be connected there too).

    Find a good place to connect the ground wire of the new battery (not on sheet metal, possibilities could be the frame, or a bracket on the engine). Connect the ground to the negative of the new battery.

    That should do it. This will take the heavy load of operating the plow off the truck's electrical system, which will save the life of several parts; and the aux. parts can be disabled in the off season.

    Obviously this is just a very generic instruction set. Each application will be slightly different. If anyone has more questions, let me know.