Second time this has happened. I go to turn my 03 MCS on and there is no electricity at all. It doesnt even try to turn, as if the battery is beyond dead. The first time, after a few tries it started up as if there was no problem at all.

The second time, car starts fine, drive to the store, come back, turn it off. 5 minutes later I go to start it up and it is totally dead again. No dim lights no anything. So the hatch is stuck closed as it is electic so I attempt to jump it through the open door, and as soon as I touch metal to the negative battery terminal (other end not yet hooked up) the lights/stereo/etc all come on and the car stars fine as if nothing were wrong, as if the battery is perfect. Why would just touching metal to the negative fix the problem?

Maybe related/maybe not, when I turned the car off the nav system then stayed on. Had to re-open the door and shut it again before it would fade off.

There is a tiny bit of moisture in the batter compartment, could this have anything to do with it? Thank you in advance smart people.

 

Try cleaning off the battery termanals and making sure the wires are touqued down tight. they can come loose even if they look like they are on

 

That would make sense, what would I use to clean off the terminals, any instructions?

 

I would just wipe them down really well with a rag. probley a dry one would be fine

 

Wire Brush. Clean the contact between the terminal and the cable. It sounds like a grounding issue.

 

Clean the terminals with a wire brush or use a battery terminal cleaner (which is simply a wire brush made specifically to fit over and inside battery terminals). Coat the terminals with a light coating of grease to help prevent corrosion, then place the terminals as far down onto the battery posts as possible and tighten them firmly. Double check the ground cable nut where the cable attaches to the body as well, remove, clean, lube and replace this piece as well to prevent any future problems.

 

It was dead again this morning so I cleaned the terminals and what do you know, it was loose. Sometimes I feel real stupid when I have to ask and it is such a simple problem. Started up fine. Thank you for all of your help.