If you remove the ground cable, you cant charge the battery...you have to have a ground.
I would "assume" that removing the neg cable, would indeed cause what you ask. But maybe those items have built in batter back up. Don't know.
Ron
Ron & Sandie
2013 Tiffin Phaeton 42LH Cummins ISL 400hp
Toad: 2011 GMC Terrain SLT2
Tow Bar: Sterling AT
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TPMS: Pressure Pro
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RETIRED!! How sweet it is....