2005 R53, Battery less than a year old

Grabbed something out of the boot last week and I must have not shut it all the way - came out the next morning to a dead battery (boot light was on for ~24 hours)

Got the battery on some cables and jumped it. Drove it around for the day and everything was fine. Couple days later, same thing - dead battery. Dropped it off at Oreilly’s (warrantied) to have them charge and check it.

In the meantime, I got a new battery from Walmart and popped it in. Car started, no issues and drove fine. Battery was/is good for days now with no issues.

Oreilly’s called me back saying they charged the battery and test came back fine (good battery) so I went back to get it. They tested my car battery, starter and alternator and are saying my alternator is bad - current not holding/charging.

Questions:
-Could the dead battery from the start take out the alternator?

-If it is a bad alternator, wouldn’t it kill the new battery I just got or is it inevitable that the new one will die? (How quickly)

what are signs of a bad alternator? I haven’t had any weird sounds, electrical gremlins, etc. I did have some intermittent starting/car dying issues over summer but when I had the car tested, battery starter and alternator were fine and it turned out to be bad fuel filter/coil pack.

Don’t have much experience (knock on wood) with alternator issues on this or any of my previous ~10 or so cars so I apologize for any ignorance on the topic. I just don’t know what to look for or want to be sure before I shell out a pretty penny having a shop put a new one in.

 

If the new Wally World battery works, the O’Reilly is wrong, or is telling tall tales to sell you an alternator. Bad alt usually has red battery light lit on dash. I had a die hard last 11 months - went to Interstate AGM.

 

ya I have read and seen that a bad alt usually shows that so my other hunch was they just don’t want to replace my battery on their dime.

However, Autozone’s alternator test showed as a “fail” too although that was like… 5 mins after I put in the new battery from Wally.

I guess I should see how the Wally battery does in a week or so?

 

My other thought is, won’t a battery show voltage is fine when they have it on hand (not in car) but needs to be tested at crank and when the car is running to really see if it’s the battery or alternator?

 

Batteries can be load tested with a tool designed for that. Each of those stores should show that to you. You can measure output from alternator by attaching a meter. Positive at the terminal by the airbox - ground almost anywhere else - strut tower for example. You should show 13.7+ to feel good about alternator. Again, those stores should show you.

 

I will have to go back. They have always tested it but via the battery terminals and never anywhere else (for alternator test)

 

Big tip: Everyone should get a Gooloo portable charger ($50 on Amazon) or similar and keep it in their MINI. It is an invaluable tool to keep from getting stuck in the middle of nowhere.

 

New battery still doing great. Got the old one back from Oreilly and they said it’s charged and good battery. I’m hesitant to put it back on but they tested the alternator again (tried with the car running, then headlights on/off, etc.) and alternator looked fine.

My hunch now is that it’s a parasitic draw which should be so fun to track down and diagnose. My first thought is the new radio I put in about 6 months ago since that’s the only change to the car, everything else is still stock/factory.

 

if the new battery is good still but the old one died it seems like you're in the clear.

test the the oreilly battery somewhere other than oreilly?

 

yup just going to monitor it and see. I had it tested there bc it was their battery and still under warranty but it’s a lost cause with them at this point.

 

Hey, if it really is the battery, then you got off easy. The 11 month old Die Hard acted funny for 3 weeks, and I had to charge it nightly in the last week, or the car would not make it thru the day. Interstate AGM from Costco ( $169 ), and all is good now. I can leave it for 3 weeks, and it will start ( 2001 e46 330CI Convertible with 180K on it ). go give it to Wally world and get your core charge back. That's all it is worth.

 

A cheap and convenient way to check if the alternator is charging is to buy one of these or similar:


This plugs into your cigarette lighter plug and since the plug is dead when the ignition is off, you can leave it in full time

 

Well the new battery died on me this morning after a couple weeks of being fine.

Car isn’t completely dead but it won’t crank over. Lights all come on and all that but not enough juice to turn over.

guess it could be the alternator after all but how would I go about checking for a parasitic draw? The only thing I could think of is the radio since that’s the only change on the otherwise stock car.

 

some really good videos on youtube for this. one i recall uses a multimeter to test for resistance across each fuse

 

i here you can test the alternator with a basic compus placed on the positive battery cable. the direction of the needle will point in the direction of charge with the engine off, then running

 

*compus

 

Why? With a $20 multimeter - you can see voltage readings……. Positive terminal in engine bay, and a good ground point.

 

multimeter is on its way today (just grabbed one on Amazon) and I guess I’ll test and start pulling fuses if weather allows it.

it’s been raining all week, car is parked on the street and the driveway has a nice incline

 

Alternator is toast after all.

Recommendations on brand to buy? I see Denso, Bosch, etc. but have read some brands are hit and miss? (But never specified which ones other than eBay/Amazon which I won’t buy from anyways)

 

I got a bosch one and it held up on my r52, Denso was oem for a time on the Gen 1 MINI Cooper S.

 

A few things to check:

1. I have replaced a few alternators on Mini's that had a cracked housing *(never an issue with charging but still worth considering as a last resort)

2. I purchased a cheap plug-in digital volt meter/USB port so I could have a more accurate idea of the charging and a added bonus of the USB. Less than $10 on Amazon.

3. The ground wire on the passenger side that goes from the mount to the engine. It is likely corroded. How do I know? Mine looked fine but I kept having voltage issues. Battery was fine and the "good" alternator was swapped to be safe. Same issues. I recalled having a ground issue on another vehicle where the wire looked fine until I cut back the sheathing and it was all green with corrosion. The mini ground was similar. You can purchase from MIni for some $50+ or make your own for a few dollars. I made my own (super cheap) and no more issues. Worth checking into as these vehicles are getting on in age..

 

Bosch Alternator

 

Alternator replaced and all is good (so far, day 3 now)

I’m sure there’s been more involved maintenance items but the fuel filter was fun over the summer… taking apart the whole front end to do the alternator was not fun (or hard though) so I have been baptized by this car so far

 

So belt started to squeak, then I heard a “flapping” noise pulling out of a parking lot.

Pulled back in, saw this (picture below)

Belt has shifted/not aligned/hitting against something so I’ll be slapping another new one on. Any tips to avoid this happening again? Everything looked lined up when I did the alternator and a new belt a few days ago and there was no shift or wobble/wiggle in any of the pulleys down there.

 

I think…

Went down to pick up a new belt and I was looking up which one/size to get and make sure it’s right. I think this was my problem and why the belt lasted a couple days:



new belt on the left, “old” belt that was just put on, on the right.

The guy must’ve grabbed the wrong belt because I remember having this discussion and the belt number he showed me on the computer matched what I had from the list on detroittuned’s site. Didn’t even think to look at the label but ya live and ya learn.

At least this time I don’t have to take apart the front end and it should be a relatively quick and easy job.