[mcarppp]

I searched and can’t find anything other suggestions aside from what I’ve already tried so here goes nothing.

I have an 07 335i MT and the battery keeps dying. I replaced the battery and that seemed to do the trick. Turns out it didn’t, but it was intermittent so I dealt with it. My dog chewed my key fob and I replaced the key fob. Once I did that, no matter how long I drove, I continued to get the message that I needed to charge my key fob. Still, months later, gives me this message. I mention this bc I have no idea if any of these issues are related at this point I’m so desperate. A short while after replacing the key fob, the new battery went completely. I replaced the battery again with another brand new BMW battery. I continue to have the issue with the battery dying and my car not starting. It’s intermittent but extremely inconvenient. I want to add that the battery has been mistakenly jumped from the physical battery by roadside people and I had left the vehicle to continue to work assuming they’d know where to jump the car from. Again, I add this bc I have no idea if any of this is related.

What else can I check? It died again a few days ago. It turns right back on with a jump but sometimes it’s not possible for me to receive a jump and take a chance that at my work over an hour away that I’ll be able to turn it on again.

Any ideas? I’m desperate for more suggestions.

[tlow98]

So next step for the battery - check the alternator. Check running vs non running voltage. Alternators can become intermittent. Are you getting a battery symbol on the dash? If so, replace alternator.

Also, check all th battery cable connections in the trunk - effectively pull the battery, inspect and reinstall. Sometimes water in the battery compartment can ruin things due to a faulty tail light seal.

On the key fob front -
Do you have comfort access?
Yes - replace the battery in the fob.
No - possible that your built-in battery is no good. Need new fob.

You buy that fob new or used? Dealer or after market?