Mine had a similar problem. Found out my ignition cylinder was bad allowing me to take my key out at any time in any position. I was turning it all the way to the left to shut my truck off, leaving the accessories on all night, allowing the battery to drain. I never thought anything of it, just thought something else was the kulprit.

The key should only come out when the truck is all the way off.
Got a new cylinder and problem went away!
Don
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1954 Chevrolet 3800 "Ella" SOLD!
My '67 stepper
"Tangerine Dream"
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