Hi Fellas,

Apologies if already asked, but I have a quick question re: Aux battery installation using the OEM cable harness kits.
Can anyone provide a harness schematic for this install. To cut this short, I can provide GM model numbers for the kit, but I thought I would throw this question out incase someone already had links/pdf docs.

Any help appreciated. Thanks.

 

I’m not sure what the OEM kit consists of, but if you’re wanting the auxiliary battery to get charged by the alternator, all you have to do is connect the positive terminals of the batteries together and run a negative cable to the engine block.

I’d recommend using 4 gauge cable at a minimum and upgrading the alternator if it’s a standard 105 amp.

 

Thanks for your input Gumby. I want to go the full OEM route, but it is dang impossible to find anyone who has done this.
I may have to end up going through GM service dept. if nobody here has done this.

 

I’m a professional, independent tech by trade - I’ve just never installed an OEM dual battery kit.

If you want to give me the part number I can try to get specific information about the installation.

 

So, doing some digging, it seems like what I need for the diagram is called a TP2 or perhaps 8BO schematic. I also see a requirement for an RPO code of 8Y8.
If that sounds like I am speaking Greek, then I understand.
If I find something, I will do the installation and perhaps post here, as I am sure that some may benefit.

 

What year is your truck?

 

2016 z71 1500 5.3L extended cab

 

The kit/schematic you want depends on what you want the auxiliary battery for, which is where the RPO codes factor in.

TP2 - Battery, auxiliary camper

8B0 - Dual battery, 600 CCA & 770 CCA

8Y8 - Dual battery, 600 CCA

I don’t know the exact applications for these options but the wiring for the charging system will remain basically the same.

I found a couple of write ups as I was searching but don’t have time to fully read through them.

https://chevroletforum.com/forum/tah...upgrade-65109/

https://www.chevyavalanchefanclub.co...ngines.136506/

If you’re intent on a GM kit, call your local dealer to source it. Oftentimes they have instructions with them or will refer you to specific posts at gmupfitter.com for installation instructions.

 

Thanks Gumby!

 

I don't seem to get the schematic to copy and paste. you can go to a GM dealer and ask them to print out the schematic, I believe it's document #4213322.