Battery Longevity?

[Aindriu]

Okay so I had a flat battery again today and it was only sitting on the drive maybe a full 30 hours or so with no start up and maybe 5-6 times I opened the car up to get something out or put something in.

I honestly think it's a disgrace and surely I must need a new battery. Please don't tell me that I have to try and limit the amount of times I go to just pop open my car to ensure I can actually drive the thing!

[chrisdaph]

I'd take the battery for a check to see if it is operational or not. If it is, put the battery on a float charger for 24 hours to recharge it. Your battery voltage readings should be:

The voltage should be 12.6v fully charged, 12.3v half-charged and 12v is getting low and the battery should be recharged or put on a float charger. This is with the engine off and the car has been at rest for a few hours.

Idle should be 12.9-13.2v and running should be 13.7-13.8v with (say) radio on.

Use a decent (Fluke) voltmeter to read the voltage, not the OBC, which will probably read low.

If you get these readings, or close to them, your alternator is probably fine as well.

If the car is not driven at least 25 miles (40 Kms) a day, I'd put it on a float charger (Schumacher or Deltran) once a week to recharge the battery.

[Spitfire007]

Check the date on the battery itself. They're usually only good for about 5 years, and these cars are VERY dependent on a properly operating electrical system.

Just go buy a new one, and make sure it's a BIG STRONG new one. Then you won't have to worry for the next 5 years, or until the alternator goes....or the cooling system...or the control arms....or the heater valve....or the valvo cover gaskets...OOPS! You're about to change to VCGs already!

Just kidding. But these cars are maintenance whores. I'm probably selling mine. It's not fun anymore to worry about it.

[heifetz17]

If the car is not driven at least 25 miles (40 Kms) a day, I'd put it on a float charger (Schumacher or Deltran) once a week to recharge the battery.

This isn't necessary. I couldn't imagine putting 25 miles on my car every day. My car is lucky to see 10 miles a day. I even use my aux ventilation up to four times a day!

A battery that's been taken care of can last 10 years or more. By taken care of, I mean making sure it sure it's clean and dry at all times, making sure the terminals are clean and making good contact with the cables, etc.

My old '98 had the original battery in it up until the last part of 2008 when I replaced it because it was getting weak. It would start the car just fine, but if I used my aux. ventilation, I would have to jump start it. The battery was 11 years old.

Also, for the record, I've compared the OBC in my old '98, and the OBC in my '01 to actual battery and charging system equipment, and both OBCs were dead on with the equipment, so I would say the OBC (at least in my case) would be an accurate way to check system voltage.

[Aindriu]

Yeah don't forget about topping the cells up with distilled water if they are low.

Acess the cells by unscrewing those little circles with the X on them. Get a torch down there and if the water looks low fill it up - Distilled Only.

Just for people that are reading and actually have a battery worth saving :rolleyes

[mojocoggo]

When I bought my car it had a 11-year-old Die Hard battery in it. It was still in perfect health but I replaced it during a shotgun-approach to troubleshooting because I was retarded back then. Also, I've run the stereo (with 200w subwoofer amp) for 6 hours straight, car started right up afterwards. I've also left the parking lights on overnight for a total of about 16 hours and it started right up after that as well.

[12v]

"Get a torch down there":lol


For those that don't know-never have a open flame(cigs included) around a battery.

[Spitfire007]

"Get a torch down there":lol


For those that don't know-never have a open flame(cigs included) around a battery.


AAAAAHHHH!!!! The enjoyment of being "lost in translation"! I love english....

[Qsilver7]

If you require a new battery...look for a class size 49 or 95 battery...they're the battery types that usually have enough RC (reserve capacity), CA (cranking amps), and CCA (cold cranking amps) to keep up and put out the juice our cars need.
************************************************** ************************************************** ***************


This is a torch...I would suggest to NOT use something like this to check your battery fluid :nono ...http://www.effectspecialist.com/imagesSP/torch2.jpg

This is a flashlight...this would be MUCH better. :thumbup: http://www.nightgear.co.uk/images/p/l/1/550/Inova-Torch-Inova-T2-48-Watt-LED-Torch-Flashlight.jpg

(just joking...we knew what you meant) :D

[Route 66]

I had to replace the original battery after purchasing the car, but I was surprised it lasted eight years.

[cazal740i]

Im confused by my battery and alternaor
I have a 07/07 dated OEm white battery
I bought a new bosch 150 amp watercooled alternaor installed 09/07
my problem is when at night and turn on my lights(parking lights,hid and fogs) my obc #9 reads 12.0v to 12.5v idle...but when I take off it gets back up to 13.0v -13.8v.
if I turn OFF fogas it goes up from 12.0v to 12.6 to 12.8v idle..Somehow My car does not like when lights r on..My cluster and interior(red mood lights)dim alot and stay a low reading....WTF is going on?..In day my car runs 13.5v-13.9v idle and accelerating....I called my indy and told him i think my alternator is dying but he said sounds like a ground issue or replace the battery.....so why is it if Im driving on freeway at NIGHT with lights on do I get a 13.6v steady but my interior lights are still dim>? shouldnt they be fully red?
I have taken battery out completely and cleaned and also wire brushed the nipples. I have made sure the neg and pos cables were sitting right and tight....So connection good.....07/07 battery dying? or alty? I start up with no problems regardless day or night...
I also at NIGht experimened by unplugging he following(HIDs, rear tails parking light and my bass amp) I still have the cluster in dim mode....Dimmer switch? well i unplugged that mf too......still dim.....so what ground issue do I have? battery...argh going crazy

[mojocoggo]

Because the alternator can't charge and supply power as well when it's spinning slow... The voltage increases when you turn the lights off because that's how electricity works. Mine is at 12V at idle as well, but anything above 1000RPM and it's up around 14V.

[cazal740i]

Because the alternator can't charge and supply power as well when it's spinning slow... The voltage increases when you turn the lights off because that's how electricity works. Mine is at 12V at idle as well, but anything above 1000RPM and it's up around 14V.
hmm...what about my cluster lighting? it stays solid for 5 secs then it flickers and dims down..and stays down..Why I started to get concern of my alty or battery..I wouldnt of even of wooried about either of them if it wasnt for the cluster dimming....

[IcemanBHE]

Sounds oddly like a LKM issue. Know anyone with a GT1 to check it out?

ahhhhhhhhhhhhhhhh I have an idea. Since youve been under your dash alot with your mods....

Check the connections to it. Take them off and reseat them.

Also check the big ground strap and make sure it tight.

[cazal740i]

Sounds oddly like a LKM issue. Know anyone with a GT1 to check it out?

ahhhhhhhhhhhhhhhh I have an idea. Since youve been under your dash alot with your mods....

Check the connections to it. Take them off and reseat them.

Also check the big ground strap and make sure it tight.
hmm..do LKm`s die?..removing the dash glovebox etc doesnt interfere with the LKM or its loaction...LKM is under the glovebox assembly on the pass side wall. I`ll try unplugging it and plugging back in..Is that what u mean by resetting it? The big ground strap...Do u mean the negative brown cable tha leads to battery?..If so I did remove the cable. I noticed the cable was pinched like the letter- L -when it was last tightened..Could I have shorted out my neg cable?...

[TxDarth]

hmm..do LKm`s die?..removing the dash glovebox etc doesnt interfere with the LKM or its loaction...LKM is under the glovebox assembly on the pass side wall. I`ll try unplugging it and plugging back in..Is that what u mean by resetting it? The big ground strap...Do u mean the negative brown cable tha leads to battery?..If so I did remove the cable. I noticed the cable was pinched like the letter- L -when it was last tightened..Could I have shorted out my neg cable?...

I think everyone is referring to the ground strap/connection for the cluster itself in the dash area. I think it is behind the cluster.....

[cazal740i]

Sounds oddly like a LKM issue. Know anyone with a GT1 to check it out?

ahhhhhhhhhhhhhhhh I have an idea. Since youve been under your dash alot with your mods....

Check the connections to it. Take them off and reseat them.

Also check the big ground strap and make sure it tight.


I think everyone is referring to the ground strap/connection for the cluster itself in the dash area. I think it is behind the cluster.....
only plugs go into the cluster..any pics of this big ground strap?

[IcemanBHE]

ok. here is what I mean. You have had the dash basically off. I know this because of the leather dash pad and other mods you have made. My thinking is somewhere you have unplugged something and not gotten it back together and made it happy.

What you are experiencing on the dash cluster lights, is a power draw, thus dimming them. This says to me that its either a power supply issue ie the LKM or a grounding issue for the cluster. Im thinking E31 here...but under the cluster about knee height of your left leg, BMW usually grounds the general module and a few other goodlies hidden here with a big ground strap. Look there. Check the LKM for "plugginess", (thats what I call propper connections). But really since these cars are multiplexed, this could really, theoretically be caused by something silly, like a non spec lighbulb in a tail light. Im serious here. This is why Im not a big proponent of changing stereos, etc. When your chasing a gremlin like this, it could lurk anywhere. But as I said....start with what you know. You had things apart. Check those first. I assume it didnt do this PRIOR to your interior mods correct? If not, then you have your answer. Its something you have replaced or changed, or messed with/upset.

[cazal740i]

ok. here is what I mean. You have had the dash basically off. I know this because of the leather dash pad and other mods you have made. My thinking is somewhere you have unplugged something and not gotten it back together and made it happy.

What you are experiencing on the dash cluster lights, is a power draw, thus dimming them. This says to me that its either a power supply issue ie the LKM or a grounding issue for the cluster. Im thinking E31 here...but under the cluster about knee height of your left leg, BMW usually grounds the general module and a few other goodlies hidden here with a big ground strap. Look there. Check the LKM for "plugginess", (thats what I call propper connections). But really since these cars are multiplexed, this could really, theoretically be caused by something silly, like a non spec lighbulb in a tail light. Im serious here. This is why Im not a big proponent of changing stereos, etc. When your chasing a gremlin like this, it could lurk anywhere. But as I said....start with what you know. You had things apart. Check those first. I assume it didnt do this PRIOR to your interior mods correct? If not, then you have your answer. Its something you have replaced or changed, or messed with/upset.
true I did a dash replacement but thae was 8 months ago. This cluster dimming just started to happen 2 weeks ago. Only electrical mods IVE done and I have already went Back and re-chcekced connections
1) tap deck to AUX mod for ipod. I removed the 16:9 screen and checked the wirring. I re-did it just in case- 1 week agp
2) I unplugged my 500 power ampfrom the battery- its been 2 weeks now.
3) I checked my Angel eyes both positive and ground connections and re-did them
4)I checked all fuses under hood and in trunk
5) i cleaned both battery termnals and made sure they were on tight
6) I went back and rechecked the QUZD brake light mod Ive done...looks good. I even unplugged both lights and still had the dimming
7) unplugged angel eyes and HID`s and still had the cluster dimming
I will remove cluster and check for this ground wiire....When u remove the dash there isnt a wire u remove..simply bolts and screws...Although u do have to remove the front airag and disconnect it.
Either LKM like u said because EDWIN did code my low beams, fogs and bright lights to come ON same time. I wonder if that coding process damaged my LKM?
When he coded my 7 a few months ago He burned out my pass side HID bulb. The Coding process of the LKm makes ur lights come ON and OFF several times in a row. That sequences of off and On burned my bulb making it look PINK.... but I was due to change he Pass side HID bul since I replaced the drivers side 1 month before. so all Edwin did was help it die sooner...lol......
so my concerns are now Ground issue and LKM....grr

[TxDarth]

You said you disconnected the power from amp before or since this started....Have you got a capacitor on the amp? I don't know because I don't have one but I have heard of people using one to prevent spikes/surges from the charging system.

Just grasping for something now.........

[cazal740i]

You said you disconnected the power from amp before or since this started....Have you got a capacitor on the amp? I don't know because I don't have one but I have heard of people using one to prevent spikes/surges from the charging system.

Just grasping for something now.........
I removed the amp to see if was a ad connection somewhere...didnt solve the trick...ut to get my battery life Imnot hooking i up till i find the power draw...I burned my alternator 2 years ago cause i didnt use a capacitor for the batery..I learned my mistake 2 years ago.....
Ive been plyn vid ames so now ill go see the lkm

[IcemanBHE]

Read where I said this wire should be. Its not behind the cluster. :) You will see the mess I mean when you take off the lower dash panel above your feet.

Also from your list....what have you done in the last 2 weeks then? One of thse might be the cause.

You can test the LKM via GT1. It should keep a list of errors if its in fact the culprit.

What happens when you do a hard reset? Battery off for 1 hour, and touch the +/- cables together for 15-30 seconds.

EDIT: 15-30 minutes. Not seconds. The magic number is 16....but round to 20-30 lol

[cazal740i]

Read where I said this wire should be. Its not behind the cluster. :) You will see the mess I mean when you take off the lower dash panel above your feet.

Also from your list....what have you done in the last 2 weeks then? One of thse might be the cause.

You can test the LKM via GT1. It should keep a list of errors if its in fact the culprit.

What happens when you do a hard reset? Battery off for 1 hour, and touch the +/- cables together for 15-30 seconds.

EDIT: 15-30 minutes. Not seconds. The magic number is 16....but round to 20-30 lol
I did nothing in beween..I did a oyster console swap but it was after the flickering began. I thought by installing the oyster consoel,glovebox, and seering hweel cover i would find a loose wore or something unplugged...I did everything perfect .. Ill try the hard reset...miight be a cool thing...Is it possible to leave the pos and neg together overnight?

[IcemanBHE]

Yes. Even better. Most problems go away after the 16 minute module goto "sleep" time and the battery off for an hour.

But I have 2 occasions where it didnt fix it. Over night worked. lol Dunno why.

Must had some super caps in somthin.

Lemme know. This is really wierd if that dont work.

Must then be a LKM or ground issue as I stated.