Mystery yellow wire

[codyjc2]

So I went to start my 3500 today and the starter battery was dead. Went ahead and replaced both batteries and I noticed a thick (maybe 8ga) yellow wire coming out of the factory harness behind the drivers side battery, obviously intended to meet the negative side of that battery. The terminal was snapped off. Does anyone know what this wire does? Everything seems to be working properly on the truck but it does have me scratching my head. I'll try to get a pic of the wire today.

 

[catch 22]

Here ya go, pretty good web site:
https://techauthorityonlinedemo.ext...selection.htm?vinString=3c6ur5fj1fg667191&s=2

 

[tuckerdog1]

catch 22,

Thanks for that link.

Tuckerdog1