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batteries and offroad lights

Discussion in 'Chevy Silverado Forum (GMC Sierra)' started by bigbuck493, Feb 16, 2014.

  1. bigbuck493

    bigbuck493 New Member

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    I have a 2010 silverado and i believe it has the snowplow prep package because it came with the amber cab light switch stock and does not have them. I am going to be installing the factory fog light setup (mine doesnt have fogs now and some idiot backed into my bumper end cap and the cost to fix it is enough to allow me to do a different setup... can never have enough lights!) which brings me to this question. I will be installing kc 6" apollo driving lights 100w (x2) or the kc daylighters driving lights 130w (x2) and within a year also would like to buy a single long range/ spot beam 130w daylighter regardless of what i go with and put it in between the other 2 also it prob wont matter but also a 60" led tailgate bar... I have only one battery running now and when i am driving at night and i go to use my windows you can see that intial drop cause the headlights to dim and i was just wondering if i was to go with this setup am i going to NEED a 2nd battery and then what setup should i go with from there? Ive seen people say isolator/ no isolator, i just want a setup that if i go to use all my stuff, if i use my windows it isnt gonna strain everything. it just bugs me lol.
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  2. TimTom64b

    TimTom64b New Member

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    Im not an expert with electrical... but I think you will want higher amp hr battery and a higher output alternator to keep everything charged. Allot of people are leaning toward the LED style lights... but I love my PIA lights. When I have all my lights running its like turning night to day...:))?
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  3. BRB46

    BRB46 New Member

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    I would think that a higher amp alternator will help. Battery shouldn't make much of a difference as it is mainly used to start the engine. Once running the alternator takes over to supply power to all systems. Make sure to run them through a relay connected with a large enough wire for the amp rating. One 130W looks to draw about 11 amps so two will be 22amps. You would want at least # 10 AWG wire and at least a 30amp relay. Don't forget an inline fuse before the relay to protect the entire circuit.
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  4. j cat

    j cat Active Member

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    when you install the lighting, pull feed off the battery block,,, place fuse there. you will need large gauge copper wire ...keep the wire runs short on the relay contacts to the lamps... the relay control wire can be small gauge wire.

    30amps should not do too much dimming ...

    If you take feed off the fuse box , then you may create a problem with power to the vehicles electrical system....GM uses to smallest gauge wires so if you pull extra power from those GM wires it can be a problem..
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  5. bigbuck493

    bigbuck493 New Member

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    i actually checked my owners manual and mine came with the emercency cab lighting package so it has the cab light switch and that circuit is rated at 30 amps which i thought is perfect if i decide to wire that because i did the amperage calculation when i saw it and noticed it was 22 amps so should i be okay running it off this? and i guess i have to see about the battery install once the lights are installed to see if i see to much strain on the system. any comments on using that factory harness or should i just use that switch with the harness KC provides or just run everything kc provides me with and use the cab light switch for any rear mounted led lights i put on in the future?
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  6. Jamm3r

    Jamm3r New Member

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    You will want to replace your stock AD-230 alternator with a larger-frame AD-244 alternator. If you get the right version of the AD-244 it is a plug and play change except that in most case a 1/2" longer serpentine belt is required. Sometimes you can get away with the stock one.

    The AD-244 will provide more amps at idle which an overwound (high amp) AD-230 will not.

    A second battery will not help matters much unless you intend to run the lights extensively when the engine is not running.
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  7. Pikey

    Pikey Moderator

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    you need to do some research before even considering a new alternator. Many of the new trucks have the alternator output controlled by the pcm. So, adding a larger alternator will net no results because the pcm will still call for the same voltage needed. Look at your negative battery cable running off your battery. If it has black box attached to it then you have the system. That box is a hall effect sensor that tells the pcm how much current you are drawing at any one time. On my truck, with a new alt, battery, and all the grounds cleaned. I can roll up all four windows, my lights dim significantly for a second while the pcm tells the alternator to ramp up output. a few seconds later my lights are bright again even with all four windows activated.

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    I would use the GM provided switch and the harness that came from kc. Chances are that it came with a relay. Just don't use KC's switch and use your own
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  8. bigbuck493

    bigbuck493 New Member

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    its funny you say that because thats what i said in the beginning! lol I said that if im driving at night and go to roll up a window the lights dim for a split second then kick back up to normal so your saying that i shouldnt do the alternator swap (wasnt really planning on it) but i might have the 170 amp. im not sure because mine has either the snoplow prep or the emergency lighting package but even say i do have the 145, would i be in danger of harming the system from putting too much load and would a 2nd battery help at all if im mainly running the stuff with truck on, thats why i was wondering about the isolator two because i thought i read that if you hook the lights up to that then the isolator will tell the alternator when to charge the 2nd one and you run your lights on that one and its a seperate ciruit.
    i dont know if this is even close to being correct i just read it and was wondering.
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  9. TimTom64b

    TimTom64b New Member

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    My lights dim briefly if I hit the peddle hard... think its when the fuel pump ramps up to increase pressure.
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  10. RayVoy

    RayVoy Active Member

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    The snowplow prep package is RPO code VYU. Check the list of RPO codes on the label on the glove box door. If VYU is there, you have the snowplow prep package.

    I'd suspect something else, the fuel pump shouldn't draw enough to dim the lights. Just cruising on the highway at an even 50 mph, the pump will run and stop to provide fuel, the lights probably don't dim under that condition.
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  11. TimTom64b

    TimTom64b New Member

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    My alternator has been acting up... will be replacing soon. Hopefully that will take care of it.
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  12. Jamm3r

    Jamm3r New Member

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    Sorry, usually your posts are spot on but I gotta disagree with you there, Pikey.

    Sure, modern alternators are regulated by the PCM. We can agree on that. The PCM determines a target voltage based mainly on temperature (lower temps=higher voltage) but also informed by the PCM's guess of the battery's state of charge. This voltage is a limit. The alternator will try to deliver enough current to reach the limit.

    There are however a number of limitations intrinsic to the alternator on how much current it can deliver. The important one for this discussion is that the physics of the rotor and stator design will limit how much current -- how many amps -- the alternator can deliver at any particular RPM and at approximately 12 volts. For stock GM alternators, the pulley size is chosen so that the alternator can deliver around 60% of its rated current at engine idle, and 100% of its rated current at typical highway cruising RPMs.

    At higher RPMs the alternator is capable of delivering more than its rated current but will overheat and fail if it does so for very long. "Overwound" alternators -- hi-amp versions of the stock alternator in the stock case -- can handle higher currents, at high rpms, without failing. They have lower output at idle however as a result of compromises that have to be made to allow for room for heavier wire.

    So if you have a stock 105 amp alternator you'll get 60 amps at idle and if you have the stock lighting turned on and the A/C blowing cold you'll use all of that, and if you turn on those KC daylighters then the alternator won't be able to keep up no matter how hard the PCM tells it to work, and so the battery will discharge.

    As a result the answer is that you have to switch to a larger-frame alternator that has higher output capacity at idle, which is what I was recommending upthread. GM has used the AD244 in a variety of configurations -- snow plow and camper packages, diesel engines, police packages -- and it's a drop in fit (except for belt length) and works great. I have one in my Suburban and have the smaller CS-130 in my pickup so I know the difference and I know they are interchangeable provided that the connectors match (and there are adapter plugs out there if they do not).

    The sensor measures battery charge current, not alternator output current. It is used to adjust charging algorithms to maximize the useful life of the battery and limit the amount of electrolyte that gets "boiled" off.
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  13. Pikey

    Pikey Moderator

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    Jamm3R thanks for the clarification. I did say that the op did need to do research about the subject. I was incorrect on my statement about there being no benefit. I don't know what I was thinking there.
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  14. bigbuck493

    bigbuck493 New Member

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    wait... question though... since iv had the truck i havent turned the A/c on yet haha. i either roll down the windows or my rear slide and the most ive done is switch on the recirculate button which isnt the same as the a/c lol and i mean i checked for the vyu and couldnt find it so i guess i have the emergency lighting package. idk if that makes a difference. i mean it has the name lighting in the package name so one might think its meant for a bunch of lights lol. but how much would the new alternator and pulley cost, could the dealer technically void my warranty installing it if i have any eletrical problems and lastly would a 100w offroad light kit be enough of a drop (60w all together) that i wouldnt have a problem with running the lights?

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    and if it helps im also getting an led third brake light and led tail lights with load resistors built in so ill be savin a little bit of energy there haha
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  15. Jamm3r

    Jamm3r New Member

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    Several hundred bucks depending on your tastes. Check the Nations Auto Electric web site for prices on various versions, or if you have a more competent local parts place who gets this stuff check with them.

    As an aside, there are dual alternator setups available that reflect the next level of this sort of thing. Not usually necessary for lights alone, but if you run a winch or an inverter it's worth considering at least.

    Who knows. Usually dealers are on your side if warranty problems come up. I'd be surprised if there were are problem.

    That's a valid question but it's hard to provide a straight answer.

    The thing is that it depends on what you're willing to put up with. Let me give you an example. I plow snow with my K2500 which has the small alternator, rated at 105 amps I think. Well it's fairly typical for me to have all the (stock) lights on and the defroster on when I'm plowing snow, and the hydraulic pump motor in the plow draws maybe 100 amps when it's running. So, when I hit the button on the control to make the plow go up or side to side, the electrical system drops to 11 volts or whatever because the alternator can't keep up. In situations where I'm moving the plow a lot and never running at speed, like plowing parking lots, the battery gradually gets more and more discharged. I'd like to replace the alternator but, well, $$$$, so it's down the list after a bunch of other things I'd like to do to the truck.

    So in your situation if you're really running trails at night and you're in a situation where you might run the lights 10, 15, 20 minutes at idle, because you're stuck in the mud or maybe because the guy ahead of you on the trail run is stuck in the mud, well, your battery will discharge. Maybe you're OK with that given the cost of an alternator, maybe not. Your call.


    It'll save you a few amps, maybe enough, who knows.
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  16. Flyinfool

    Flyinfool New Member

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    If you used your defroster with the temperature above 32°F then you have been using the A/C. The A//C comes on with the defroster to dehumidify the air that is blowing at the windshield.

    LED bulbs with load resistors will not save any power. The sole purpose of the load resistor is to draw additional power so that amp draw stays the same as what it was with the original incandescent bulb. Load resistors are used so that the computer monitoring the amp draw will not see the reduced amp draw of the LED and indicate an out bulb.
    #16

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