I have a 2007 base RDX w. 127K and serviced only at the dealer. Today as I'm about to leave work the remote did not open the doors. I used the key in the door. Then I enter the key in the ignition and zero.....No power.
This is a new battery (1 year old --last service 500 amps). So I open the hood and start fudging around. I bumped the battery poles, and checked the fuse box. Lots of grease on the poles. Then I see a small light in the cabin. I go in and crank it. It started!
Then I realized that the odometer/mpg were cleared, and the radio asked for the code. I came home and found my stereo code enter it, and it got started too.
It seems that the battery had reset, as if when you disconnect it.
But the car was inside the UG garage at work and it had not been tampered.
That was a very weird electrical episode. Nothing scares me more than electrical problems. Very hard to troubleshoot.

 

Tighter the terminals . If they won't tighten anymore you may need new cables, simple as that check to insure there's no corrosion on the cables as well

 

You're right, the positive was loose. But the nut is tight all the way.
So I just banged it down and it seems a bit tighter now. However I'll have to fix it. I may have to bend the metal a bit to make it to synch tight with the nut.
I had cleaned some cable corrosion a couple of years ago with baking soda, so that's clean.

 

Don't do what you just said. Can cause more damage than good. Buy this battery post shim and call it a day.

https://www.amazon.com/Schumacher-BA.../dp/B0060YI0YS