First off, I want to apologize for starting another thread on this as I have read numerous threads on this, but most threads are ancient and don't think most would respond.

I have a 2005 MCSa w/ 138,xxx on the odometer. The car hasn't been driven much over the last few months due to me having a front-end accident rendering the Mini unfit for driving (in the eyes of the law, the car was mechanically fine). Now that I've graduated back in December and finally working, I begun fixing the ole boy and got it to a point that it is safe to drive.

Now to my current issue. I started the car yesterday after installing my new bumper reinforcement and headlight, and I took it for a spin. Drove and started all day without issue (I'd say I started it 5-6 times). Then, this morning, I went to fire it up so I could drive it to the paint shop to finish my body work, and it wouldn't start. I can hear the fuel pump activating and a single click, but the starter doesn't sound like it's turning over. The battery is only 3 months old and tested at about 12-13v. It's holding a charge. I tried jumping the car off of my bro's SAAB, but I got nothing. I let the jumper cables stay attached from the battery in the SAAB to the posts in the MINI for about 15 minutes and still nothing... Just the fuel pump activating and a single click. I thought about the alternator, but the car should still start with jumper cables on if the alternator was bad.

I am suspecting it's the starter motor/solenoid that needs replaced, probably from sitting around the last 7 months, but I wanted to get the opinions of the forum before I spend another dime on this car. I have so much still to put into it; can't afford to just throw money into the dark.

Also, one weird thing I've noticed is the driver side window lowers itself every time I try to start the car. The electronics inside the car goes a little crazy after it fails to start. The battery I installed in it is an Everstart H5 battery, rated at 800 CCA @ 32 degrees, 675 CCA @ 0 degrees.

 

12-13 volts is pretty bad for a "new" battery...new should be 13.5+
It is either not fully charged or weak...
Know you tried with your friends car....but it sounds like you have low voltage/amps...
I would do two maybe 3 things...all free first..
Take the battery OUT...have it tested...just a voltmeter does not tell the whole story...they should load test it, and charge it up for you...
Next, the box, next too the battery in the trunk...be careful, it has an explosive charge, aka, a "squib" in it, kinda like an airbag...it disconnects the battery in a collision...they sometimes get wet and corrode.... Limits voltage going through the connection...
Next, check your grounds...both on the battery, but more importantly the one on the from passenger side engine mount..
If that fails, might be time for a starter
Windows dropping/etc after a failed start is typical from low voltage cranking..
Might be something simple/free...also make sure the plugs on the ecu a in tight...an impact could have lousened them up a bit...
Next...look at the

 

Thank for the reply and I'll definitely check all the things you mentioned. I'll run the battery in tomorrow and have it tested and I'll be under the car checking all of the wiring... I read in another thread to check the wiring harnesses cause critters like to get up in engine bays this time of year... I've had this problem before when a mouse or something chewed through my speed sensor connected to the front brake. I live out in the sticks, so there are critters everywhere.

 

I went to remove the battery from the well and noticed the negative terminal was covered in about a 1/16" of corrosion. The wire was fine but the post and the connection was covered. The weird thing is that I had the battery uninstalled while the car was sitting, so all of the corrosion formed from on the one day I drove it. It wasn't there went I tested it with the voltmeter. Not sure if this was the cause of the car not starting yet, but it'd be sweet if a $3 wire brush was all this costed me.

 

Whelp, this is embarrassing... Cleaning off the corrosion from the negative terminal did the trick. My Bernie started right up. Should've been the first thing I checked and now I'm embarrassed I started a thread on it! lol

First step if your vehicle won't start: check the battery posts for corrosion and clean them if corrosion is present!

 

Glad to hear it was an easy fix. Those are the best ones.