skeematics

"Increased Battery Discharge" was displayed on the dashboard screen. Took the car to a indi BMW shop. They said the Battery ($290) and Battery Negative Cable ($227) both need replacement.

My car is a 2007 still equipped with original battery so it may make sense that its due for a replacement. But the negative battery cable doesn't make much sense to me. The mechanic is saying that the negative cable is causing the battery to drain by sending wrong information to the voltage detection computer.

Before i commit to doing this pricey work, i would like to know if any you guys experienced this.

I've had problems before with the Comfort Access door handle draining my battery which was fixed, now this negative battery cable replacement is puzzling.

Gilgorm

Wow, a 07 with an original battery. Change the battery first and get a second opinion on the cable. Are they referring to the recall on the "Battery Cable Insulated Bulkhead Connector" for MY 04-10 5 Series? If they are it is a no-cost change for you at any BMW dealer.

luigi524td

The cable being referred to as the "Negative Cable" is the IBS (Intelligent Battery Sensor) and integral to the complex battery and charging system on our cars. You probably remember the "old days" when the negative cable was also called the "ground". You could buy one for a couple of dollars.
That was then - this is now

skeematics

I already took care of the recall. The recall had to do with the Positive cable only. This ground (IBS) cable is different. What if i change the battery only to have it quickly drained again by a faulty IBS cable?

skeematics

What if its my factory alarm causing the battery drainage? I notice the "Increased Battery Discharge" message does not appear when i dont arm the car.

tonyb635

I had the same thing on my 08 10 months ago. The msg often came after a long weekend where I was not driving the car, or I opened the doors often and did not drive it. I actually replaced the battery with one from AutoZone that had the Ca and CCa numbers matching exactly and all has been just fine. I am not sure why he is telling you to change the cable. Maybe it needs to be changed. Did they say exactly why this has to be done? Maybe he noticed some damaged...? If not, I would probably just go with a battery swap. The dealer wanted 650.00 to change my battery, there was NO WAY!!!

skeematics

You got a battery from Autozone?!?! I was told by many that its not possible to get a battery from anyone but BMW. And even getting a new BMW battery required programming so that it would work!! How is this possible?!? Tell me how you did this!!

ETNav382

Go to Autozone,
Buy replacement battery
Replace old battery
Go see John@motorcepts for programming or not

DONE!

nomis_nehc

Actually, if you want the OEM battery, John can get it too if I remember correctly. I think he sells it for around or under $250.

DonoVain

I had same issue and also own 07 BMW 530i. I purchased a battery from Sear and it took care of the problem. Never saw that waring again.