2004 2500HD Second battery

2002HeavyChevy · December 26, 2004

Hey all,

I am just writing to find out about the 2004 2500hd's second battery. I currently have a 2002 2500HD and the second battery is near the hood arm by the passenger side firewall but my fathers 2004 2500HD doesnt have one. He is concerned that he might have gotten ripped off at the dealership which could be the case and thus we need to have this fixed. How we came about checking for it was that he placed the plow on today and tried it out and the plow lights seem to dim an aweful lot when he moves the plow in any direction and up and down. I said check the second battery and we couldnt find it.....well we looked where mine was located. Is it located some where different? Was it an option that he didnt get? Mine does not have a plow or plow package on it and he is not pleased that this wouldnt have gotten included in the "package" that he got when he purchased the truck new from the dealer with the plow and everyting. We have the exact same truck just different years. Any help with this would be great, with not only where the battery could be but also what could be done to stop the power loss to the lights, ie. the dimming.

Thanks again!

Chris

Haulin' 8.1 · December 26, 2004

It is a separate option, it would be in the same spot. See this post: http://www.gm-trucks.com/forums/index.php?...topic=34542&hl=

Note the two option codes listed by Builder Paul, one of these will be listed on the option list build sticker inside the glove box if it's supposed to have been there. It would be more trouble than worth the effort to remove it for a free battery by the dealer in my opinion.

Vernon

BBSilverado · December 26, 2004

the dual battery was a separate option and it only came standard with the diesel, the plow prep package didn't automatically come with dual batts.

There are two different dual battery setups:

code TP2 had a isolated auxiliarly battery and

code TQ3 had a non-isolated second battery.

The diesels used option TQ3, for plowing you should use option TP2 and put the plows leads on the aux. battery.

chevhot · December 27, 2004

the dual battery was a separate option and it only came standard with the diesel, the plow prep package didn't automatically come with dual batts.
There are two different dual battery setups:

code TP2 had a isolated auxiliarly battery and

code TQ3 had a non-isolated second battery.

The diesels used option TQ3, for plowing you should use option TP2 and put the plows leads on the aux. battery.

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i have an 04 with duel batt's and i also have a plow on it also and the lights dimm alot is it because its not hooked up to the aux batt?

Jacqson · December 27, 2004

the dual battery was a separate option and it only came standard with the diesel, the plow prep package didn't automatically come with dual batts.
There are two different dual battery setups:

code TP2 had a isolated auxiliarly battery and

code TQ3 had a non-isolated second battery.

The diesels used option TQ3, for plowing you should use option TP2 and put the plows leads on the aux. battery.

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i have an 04 with duel batt's and i also have a plow on it also and the lights dimm alot is it because its not hooked up to the aux batt?

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IMHO I think that it could possibly be more of an Alternator problem than a battery problem because your Alternator can't keep up with the drain on your batteries or you may have a defective cell(s) in one or both of your batteries. Dual batteries give you more storage and starting capacity. Both the TP2 and the TQ3 options work the same when the vehicle is running, the difference is when your vehicle is off. TP2 separates the connection to the batteries so that if one discharges or has an electrical drain for some reason the other will stay charged. If the same thing happens with the TQ3 option both of the batteries will discharge. Lots of guys that have winches and other accessories will isolate there batteries in case they need to winch out and the truck is not running, they can use the power of one battery to winch out and once they are clear they can use the other battery to try and start the truck. If there was no isolator you could use all your battery power getting out and have non to start the truck.Sorry for being so long winded. Hope this helps

BBSilverado · December 27, 2004

With the isolated dual battery setup (TP2) every time a heavy load is applied to the main battery the isolation relay will open the connection if the main voltage falls below 11.0 volts, thats is why your aux. battery will not start the truck if the main battery is dead unless you use jumpers cables and jump your main from your aux. battery.

If your plow is connected to the main battery then every time you hit the plow controls the aux. battery is being temporarly disconeected from the main and thus making it act like you only have one battery. That is why the plow should be on the aux. batt if you have a TP2 setup. with the TQ3 setup it doesn't matter witch battey you connect the plow to and you always have the power of both running your equipment, and you have a better chance of getting 2 dead batteries. sorry about the long post but I hopes that clears things up

2002HeavyChevy · December 27, 2004

Once again genteleman you have helped me outta a tight spot. As fathers might have it, and i know some of you are like this, it takes a thread like this to convince him of any wrong doing or that "he" didnt get the option added in. I did a search a while ago and came up with a second battery aftermarket setup that you can get....anyone care to send me a link on that......I will search but incase anyone else searches and finds this thread they wont have to look any further. Again thanks again for all the help, hopefully this will ease his mind. LOL yeah right!

Chris

BBSilverado · December 27, 2004

I can tell you the aux. battery tray is GM part no. 15705102 and that will fit 99-05 silverado and sierra.

dcalex · December 27, 2004

Just another thought. The TP2 is basically a camper setup and does just what the guys say. It also will shut down after 20 mins. if the truck is not running to avoid running your batts down inadvertantly. If I were plowing, I would have gotten the 2nd alternator too, but we all know about hindsight.

dewfpo · December 28, 2004

There's also the alternator upgrade option from the 105 amp unit to the 145 amp unit. (8C5)

When I ordered my truck I ordered the second battery and the higher amp alt. just for this reason.

DEWFPO

builderpaul · December 28, 2004

There's also the alternator upgrade option from the 105 amp unit to the 145 amp unit. (8C5)

When I ordered my truck I ordered the second battery and the higher amp alt. just for this reason.

DEWFPO

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The 145 amp comes with the plow prep option

chevhot · December 28, 2004

i have the 145 amp alt and duel batts in my 8.1 but when i lift the blade the lights dim i called fisher and they told me that it didnt matter what batt it was hooked up to fisher alway hooks up to main batt the plow motor draws alot of amps

dewfpo · December 29, 2004

Chevhot,

Which dual battery option do you have? TP2 isolated battery or TQ3 non-solated?

DEWFPO

chevhot · December 30, 2004

im not to sure i was looking at the build sheet it said hd aux batt and

145 amp i need to look for rpo code

BBSilverado · December 30, 2004

There's also the alternator upgrade option from the 105 amp unit to the 145 amp unit. (8C5)

When I ordered my truck I ordered the second battery and the higher amp alt. just for this reason.

DEWFPO

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