[sumisu]

Ok. I know this has been discussed ad nauseam everywhere but I'm still having trouble finding some clear information. So I'm having trouble with my battery draining out easily and the car not starting. A 2006 325xi wagon I purchase in June. The car had an Interstate lead acid battery and not the OEM - so it has been changed. The day I bought the car my kids were playing with all the power windows and seats and drained it out in an afternoon. I load tested the Interstate battery then and it passed. However, it was dead the other day for basically not reason but a few short trips the previous day. I have some concern about possible parasitic drain or something, so I don't want to drop extra cash on an OEM battery right now.

Questions:

1. Battery Type: Were the oem batteries AGM or lead acid in 2006? BMW parts department quoted only lead acid batteries ( about 250 plus tax ), but Interstate quoted me AGM ( about the same price ). I assuming the BMW guys would know best. Anyone?

2. Registration: I installed a new battery (lead acid ) this morning from Batteries Plus (Duracell, made by East Penn ) and it works fine so far. However, I tried to register the new battery with my ECS tuning scan tool and I get an error telling me it cannot connect the DME because terminal 15 is not on or something. Anyone familiar with that? What is terminal 15?

Thanks!! If I can't figure this out, I'll just pay the BMW Service Dept. battery registration tax and be done with this. Good gosh - no reason you shouldn't be able to do this from the drivers seat control center.

[John 070]

I believe only the M3's got the AGMs back in the day, and the batteries were black, not white....

[fun2drive]

Very useful for BMW to add registration to their needless list of dealer only servicing. Don't get carried away with the battery registration. What it does is this.
The IBS is more than a sensor it is also a processor storing parameters that it sends to the DME. The DME controls the voltage output of the alternator. BMW has not posted the numbers for the % of improvement of non registered BMWs. There are members out there that have never registered their battery and all it does is shorten the battery life an unknown amount. Sure sounds like a parasitic loss and they are a pain to track down given the trunk needs to be open to do this...

[Sgt Fox]

I think terminal 15 is having the ignition on but not running. Try again hitting the start button twice but not starting the car.

[fazman]

Originally Posted by sumisu

Ok. I know this has been discussed ad nauseam everywhere but I'm still having trouble finding some clear information. So I'm having trouble with my battery draining out easily and the car not starting. A 2006 325xi wagon I purchase in June. The car had an Interstate lead acid battery and not the OEM - so it has been changed. The day I bought the car my kids were playing with all the power windows and seats and drained it out in an afternoon. I load tested the Interstate battery then and it passed. However, it was dead the other day for basically not reason but a few short trips the previous day. I have some concern about possible parasitic drain or something, so I don't want to drop extra cash on an OEM battery right now.

Questions:

1. Battery Type: Were the oem batteries AGM or lead acid in 2006? BMW parts department quoted only lead acid batteries ( about 250 plus tax ), but Interstate quoted me AGM ( about the same price ). I assuming the BMW guys would know best. Anyone?

2. Registration: I installed a new battery (lead acid ) this morning from Batteries Plus (Duracell, made by East Penn ) and it works fine so far. However, I tried to register the new battery with my ECS tuning scan tool and I get an error telling me it cannot connect the DME because terminal 15 is not on or something. Anyone familiar with that? What is terminal 15?

Thanks!! If I can't figure this out, I'll just pay the BMW Service Dept. battery registration tax and be done with this. Good gosh - no reason you shouldn't be able to do this from the drivers seat control center.

Check out your regional section to see if someone with an obd2 cable and inpa can check to see what AH rating battery your car was "coded" for.

I'm willing to guess you don't have a correctly coded battery (easy fix if you have a local coder who will code/register the battery and turn on the common convience features of the car for $50.

go back to the store where you purchase the new battery and ask them:
1) Is this an AGM or non-AGM battery?
2) What is the AH rating of this battery?

with those two pieces of info you are set to get your car coded. If they have no idea what to tell u the AH rating is, ask them:
1) What size group is the battery? H6, H7, H8, something else?
2) what is the RC (Reserve Capacity) of this battery? You can calculate the AH from the RC

AH = (RC / 2) + 16
round that number up or down to the neatest 10th's and that is what you code the car as.

For example, if the battery is an 84 AH, i would code the car as an 80 AH profile.
if the battery was a 85 AH, i would round up to a 90 AH profile to code the car.

[Underground6t9]

Check alternator sounds like that might be the culprit

[mweisdorfer]

Originally Posted by sumisu

Ok. I know this has been discussed ad nauseam everywhere but I'm still having trouble finding some clear information. So I'm having trouble with my battery draining out easily and the car not starting. A 2006 325xi wagon I purchase in June. The car had an Interstate lead acid battery and not the OEM - so it has been changed. The day I bought the car my kids were playing with all the power windows and seats and drained it out in an afternoon. I load tested the Interstate battery then and it passed. However, it was dead the other day for basically not reason but a few short trips the previous day. I have some concern about possible parasitic drain or something, so I don't want to drop extra cash on an OEM battery right now.

Questions:

1. Battery Type: Were the oem batteries AGM or lead acid in 2006? BMW parts department quoted only lead acid batteries ( about 250 plus tax ), but Interstate quoted me AGM ( about the same price ). I assuming the BMW guys would know best. Anyone?

2. Registration: I installed a new battery (lead acid ) this morning from Batteries Plus (Duracell, made by East Penn ) and it works fine so far. However, I tried to register the new battery with my ECS tuning scan tool and I get an error telling me it cannot connect the DME because terminal 15 is not on or something. Anyone familiar with that? What is terminal 15?

Thanks!! If I can't figure this out, I'll just pay the BMW Service Dept. battery registration tax and be done with this. Good gosh - no reason you shouldn't be able to do this from the drivers seat control center.

I'd run an alternator test on it.

The OEM battery was a led/acid battery 720 amp

No AGM's were installed in those days unless it was an M3

Best battery for your $$$ is an AutoZone, Duralast Gold.

I've had mine for 3 plus years, no issues.

You don't need an AGM unless your running a serious after mkt stereo that has a GPS etc.

Just my 2 cents

[sunny]

AGM battery is also less outgassing.

[kfriceman]

Originally Posted by sunny

AGM battery is also less outgassing.

AGM batteries do not vent, they are sealed.

-Kevin

[johnson47376]

Originally Posted by kfriceman

AGM batteries do not vent, they are sealed.

-Kevin

I don't believe this is 100% true as my AGM battery is vented.

AGM is a type of lead acid battery. I only say this incase you go to a store and the salesman is a "know-it-all" and tries to make you feel dumb. Personal experience with this.

The standard batteries that you find in many cars are wet cell aka flooded.

[Wilt]

Originally Posted by Sgt Fox

I think terminal 15 is having the ignition on but not running. Try again hitting the start button twice but not starting the car.

^ Terminal 15 is active when the ignition is switched on (engine not necessarily running)

[galahad05]

Love this site.

Helpful info all in one thread.

[kfriceman]

Originally Posted by johnson47376

I don't believe this is 100% true as my AGM battery is vented.

AGM is a type of lead acid battery. I only say this incase you go to a store and the salesman is a "know-it-all" and tries to make you feel dumb. Personal experience with this.

The standard batteries that you find in many cars are wet cell aka flooded.

"Even though your batteries [AGM] are normally sealed, they actually do have a venting system integrated into the case top. In the event of an overcharge condition, it is possible for excess pressure to build up inside your battery. Your new batteries are equipped with check valves that are engineered to open at between 2-3 PSI depending upon the specific brand. What will be expelled is hydrogen gas, and you want to vent that as it is quite explosive."

The venting you see is a safeguard, under normal operations the battery remains in a sealed state.

-Kevin