Has anyone seen this?

My wife called me at work, said the car wouldn't start, the brake wouldn't depress. I've known this to be an indication that the battery was dead. Now, we just had it in the shop to replace the thermostat and clean the injection system (my wife had spent 5 months putting low-octane gas in it). There were no indications or warning lights that the alternator was not working.

I went home and, yes, brake was locked up, and when I pressed the start button, everything died. So I took out the battery and took it to the local shop. Turns out the battery is fine, but depleted, so I had them charge it and took it back home and stuck it back in the Mini to see if I had any indications that the battery wasn't getting a charge.

Pressed start, and everything shut off as before. Dead battery? I took a close look at the terminals, maybe I missed something, a broken connection, some corrosion, something. Everything looked fine, but I figured I would take out the battery again, forgetting that the key was still in the slot. When I started pulling the Positive connector off, suddenly the headlights turned on, I heard the 'alert' trill that the door was open and the key was in.

I jumped in and the Mini started right up. So I'm stuck. I don't know what the problem is; the battery is fine and the connections appear to be fine as well. I was thinking maybe on the other end of the cables, near the starter there might be a problem, but I don't think I was applying enough force to in any way jiggle the connections at that end, but I'm not familiar with how far down that connection is.

Has anyone seen anything that might explain this, or do I have some fluke situation? Has anyone had issues with the system not giving the "battery not charging" warning when the battery was, in fact, not charging? Or do the battery cables fail in other areas besides the terminal connections?

My concern is that, no I didn't actually fix the problem with my awesome Rico Suave hands, and that I'm going to get 40 miles down the road and everything is going to die on me again. But if it is something simple I don't want to spend a grand at the mechanic if I don't need to.

Any help would be appreciated.

 

An update: it happened again while my wife was at the store. Once again, I was able to fix it by twisting the positive cable about 10 degrees around the terminal. This doesn't make much sense to me, the terminal and connector are clean, there is no tension on the battery cable itself and the terminal housing on the battery appears solid. Is there any way for the cable to get crimped or fail in the body of the wire that would explain this?

 

Batteries can fail internally...the lead plates are crimped/soldered to the lugs on top...maybe s jiggle tightens it up....so it can work...

 

Yeah, I'm hoping that is all that it is. I had O'reilly's check it out and they didn't find anything, it worked fine on their charger. But, I don't know if they would necessarily be able to tell if that was the problem. I also tore up part of the covering for the battery where it meets the windshield, the soft rubbery part was sun rotted and, even though cool, just came apart like gum when I was putting it back on. So that's something else, although its just cosmetic.

I'll be taking it out again and running to the shop to see if they can mess with it and tell if that is it or not later today. Thanks for the help!

 

Even though your battery terminals may "look" clean, there's actually a thin film of lead oxide acting as an insulator.

Get a wire battery terminal cleaner and clean the terminals and connectors until shiny, then put back together.

I'll bet your problem will be gone.