2012 e92 M3: "increased emissions" and battery - Need the best unit for codes/battery

[Gunnder]

Hi Guys,
fairly new to the forums, but I've had my 2012 e92 M3 since early 2015. I guess why I've never posted before is that the cars been solid for almost 3 years, so I've had no reason to log in. Just been really enjoying the car and put about 20,000 km over those 3 years. I use my car for weekend/evening fun only, not DD. But being in Canada right now it is very cold and the car was parked for a month since last being driven Which brings me to the real first issues with the car:

Last month before it got really cold, I fired it up for a quick drive around town and I got the "battery discharging while car is stopped" error message. I read around and seems like this just means I need a new battery and it needs to be coded in. Probably still original battery, but no way of knowing since I was not the original owner. I drove the car for about an hour to charge up the battery. The next day I turned the car on to check and the error message was gone. Perfect.

Then a few days ago I fired it up again just to check and the error message was back along with the "increased emissions" error message. Hmmm... again I read around a whole lot and many things can be related to this from simple O2 sensors to more complex things. I even read that a low battery can throw this "increased emissions" error as well, as one user changed the battery and the "increased emissions" message went away.

Would love some thoughts and opinions on this.

And also what is the best and most comprehensive unit to buy to diagnose these issues. I guess I need the exact code the "increased emissions" is throwing out and I need a unit that will also code the battery once I replace it.

Is Carly the best for this? I believe Carly will work on me e92 M3 and will show all codes and program the battery. Are there other better units? I read some of them don't program the battery. I don't want the cheapest and am prepared to pay for a better unit that is fully compatible with my e92 M3 and allows diagnosing of all the codes and programming, etc. Thank you all!

[IanB22]

Can't answer every question, but it's time for a new battery.
Start there, work your way back to no messages

[eatsleepboost]

Carly will certainly do it. I got my wireless dongle off Amazon and downloaded the app on my phone. I also used Carly to do some coding on the car. There are many options that you can change using it. Some cost a few bucks but you can do every feature, have the app, and the wireless obd connector for under 200$

[Gunnder]

Just wanted to update this post since I forgot about it. It may help someone in the future. Basically all it was was a partially drained battery from it sitting in the garage all winter. I got the codes cleared and drove it a bunch of times and all is well. The next winter I put it on a battery tender and never had the issue.

[Siajoon]

Originally Posted by Gunnder

Just wanted to update this post since I forgot about it. It may help someone in the future. Basically all it was was a partially drained battery from it sitting in the garage all winter. I got the codes cleared and drove it a bunch of times and all is well. The next winter I put it on a battery tender and never had the issue.

Don't wait until something bad happens to the car to post back! Let us know about the good times too

Oh and this thread is useless without a picture of your beast by the way.. juuuust saying