Voltage at speaker

[Cconway25]

I have a 16 2500 bighorn, long story short batteries would die if truck sat more then 36 hrs..found that my right rear speaker would thump hooking up a battery charger with key in my pocket.. when trucks running the right rear speaker wire shows 2 volts..truck off shows 4 volts truck in sleep mode I'm showing 12.6 volts at my right rear speaker wire, I ended up cutting and taping the wires and never had dead batteries since, anyone ever have somthing like this happen? Is there a fix? I want to use that speaker again
thanks

 

[Jim BB]

i would try and chase the speaker wire to see what is feeding it the voltage! and try and find a schematic of the wiring for the system !

 

[2020PW]

What stereo is in it? Do you have an amp system?

 

[Cconway25]

What stereo is in it? Do you have an amp system?

I had a neighbor install an amp and subs under the seat, a year before this issue srarted, worked fine, amps wired to the battery with one of the aux switches for switching it on, but it's not powered or hooked up anymore that was my first thought that it was that instalation when my batteries first died, so I disconnected everthing bought new batteries (it was time).. that's when I noticed the speaker thump the first time, then when the new batteries died after the truck sat 2 days I heard it thump hooking up a charger, I taped the right rear wires up then about a year ago and kinda forgot.. haven't had an issue..but I checked yesterday and it still gets battery voltage 12.6 at the right rear speaker wires when the truck goes into sleep mode a few minutes after shutting it off...I'm guessing it's coming out of the 8.4 head unit