pavjayt

Yesterday while I was doing usual errands and driving back home, the iDrive suddenly disappeared, thinking that this might be usual iDrive being stuck issue, I tried to reset it by keeping the volume knob pressed for a while, but this didnt do the trick. A whole lot of issues all fired at the same time one by one, at first the warning lights came on for all on the dashboard, the car went into limp mode, climate control is completely off, no lights on the gear shift knob. 4x4, ABS, DSC etc warning started to cycle through on the dashboard. I never felt how it would feel in limp mode, but its like stuck in low gear and the steering is a bit heavy as well. None of the dashboard gauges work except for the engine speed. Temperatures went up with warning light coming as well (guessing that this is because of pump not being operational due to electrical shutdown). The car kept shutting down itself and after like 30s kept starting again with engine fan blowing and everything On (including headlights), but then shuts off and goes to limp mode again for a bit. Turning on the headlights switch didnt do anything, they are Off. Slowly, but carefully made it home. Kept it on a charger overnight (started at 25%), but it is still at 25% in the morning. Using a 7.5A charger (Nocco Genius), voltage readings while charging at the terminals under the hood are at 11.8V, switched the charger to supply mode (13.5V, 5A), it still shows 11.8V on the DMM.

I am more leaning towards a weak or dying battery. I know that the battery is original BMW one but not sure if its the one that came with the car, I bought it second hand about 4 years ago, but I can tell for sure that the battery was not at its 100% functioning state (kept discharging quickly) since the beginning and I have been keeping it on the charger most of the time whenever I get a chance.

Just though would check with the community about their experiences.

donpb

I don't have a fancy charger but if it stays that long at 25%, it will fail the battery. I have a 6A charger and it fully charges within a few hours. Sounds like your battery has a shorted cell.

pavjayt

Thanks for your quick reply, mine always took many hours to fully charge even on AGM mode on my charger and thought that might be normal for an AGM battery.

Any downside by going with normal battery vs AGM? Any insights on what kind of tweaks one needs to do with INPA going with a normal battery?

donpb

I've always used a normal battery without issue. Even the dealer said it was fine. I believe the AGMs hold a much longer storage charge and so if your car sits around a lot, that might be beneficial.

Alpine

If the battery is at least 4 years old then on the good side it's just the battery that's old and time for a simple replacement. This forum has several useful guides on how you can do it, it's a 10-15 minute job at most...

... but as you have an E61 do check in the battery well and right at the bottom of the spare wheel cavity that there is not a drop of water down there as a battery drain is often the first sign of problems from water ingression from the sunroof.

pavjayt

Thanks for the water leak point, I took care of this couple of years ago by removing the end stopper for the drain tubes under the car. But I did have this water ingression and battery drain issue couple of times. For the past 6 months, the car is being parked in garage and havent driven in rain at all. I am going with H8 Exide battery from Homedepot and code car for non AGM battery.

pavjayt

Quick question
The homedepot battery that are available for pickup at both stores near me are more than a year old, so I am not going to buy them. Local costco has H8 with 10/20 date (excellent), but here are the specs breakdown

Homedepot 950(CCA) 90(AH) 170(RC)
Costco 730 100 175
OEM 850 92 not sure

I dont think it will be a problem if I go with Costco one, but would like to hear your thoughts as well.

pavjayt

Just got a chance to take out the battery and looks like it definitely has seen its last days since the MFG date is Jan 2012. Will get a new one first thing in the morning.

pavjayt

Ok, just replaced the battery and the problem still persists. The car goes to park and the gear shift lever is disabled soon like after a minute of driving (involving taking it out of garage), messages start off with 4x4 warning, DSC warning and then followed by transmission failure. Looks like its time to drop it off with a mechanic. Any suggestions for a good reliable non stealer mechanic in or around Dublin/Pleasanton/San Ramon?

Much appreciate your suggestions.

donpb

I'm not too sure about that 730 CCA. Seems a tad bit low. From your car sitting around for so long, a lot more could be going on besides just the battery. You need to read the DTCs using a BMW code reader.

Also, if your old battery was super low, it can take awhile for all of the craziness to shake out after you install a new battery.