318ti.org forum

Go Back   318ti.org forum > Technical, Maintenance and Modifications > Electrical

Notices

Electrical All wiring questions.

.
» Recent Threads
1999 M-Sport For Sale
12-31-2023 05:10 PM
Last post by Coop540iT
03-23-2024 06:39 PM
1 Replies, 96,918 Views
Once again 318ti owner...
03-20-2024 12:39 PM
Last post by two30grain
03-22-2024 02:04 PM
1 Replies, 59,890 Views
What brakes do I...
03-20-2024 03:27 PM
Last post by huirtera
03-20-2024 03:27 PM
0 Replies, 57,301 Views
M50+manual swap bastard...
03-01-2024 11:00 PM
Last post by Andy318
03-18-2024 02:34 PM
3 Replies, 132,405 Views
Reply Share/Bookmark
 
Thread Tools Display Modes
Old 09-11-2010, 06:47 PM   #1
318ti
Member
 
318ti's Avatar
 
Join Date: Dec 2004
Location: Toronto Canada
Posts: 61
iTrader: (0)
Default Won't Start after charging battery

Hi All

Hoping you could confirm my thoughts. Went out this morning to start the car and I had zero dashlights. Tried to start the car and wouldn't even click the solenoid. Sigh... I gave it a boost and it started right away. When I removed the negative lead from the booster cables, the engine died. Hmmmm. Started it again and same thing.

Metered the baterery and it was 11.5. Charged it and the charger said it was at 85% capacity, Charged to 100% in 10 or 15 min.... already suspicious. Same thing. No dash lights and no start. Now the battery charger said it was at 10% capacity. (WTF) Then re did the connection and it was at 65% capacity. All with the battery cables disconnected from the car. Put an ameter between the Plus post and the lead and read 0 draw on the current with key off.

I'm thinking battery, but likely an altenator as well. Thoughts?


Peter - powerless in Toronto
__________________
_____________________________
Peter
1999 318ti
_____________________________
318ti is offline   Reply With Quote
Old 09-11-2010, 07:19 PM   #2
cooljess76
NOBODY F's with the Jesus
 
cooljess76's Avatar
 
Join Date: Oct 2006
Location: Ventura California
Posts: 7,824
iTrader: (6)
Default

Check the other end of the negative cable where it mounts to the chassis. Also, check the engine ground. It's located on the passenger side motor mount arm. Clean and reattach both ends of the cables.
cooljess76 is offline   Reply With Quote
Old 09-11-2010, 09:20 PM   #3
318ti
Member
 
318ti's Avatar
 
Join Date: Dec 2004
Location: Toronto Canada
Posts: 61
iTrader: (0)
Default

Thanks Cooljess76

I did check and they were fine. Finally broke down and bought a battery load tester.
At rest the battery is fine. Under load 1v. If I boost the car and let it idle for a bit i can remove the booster battery. When I put on a load it stalls the car. If I leave the booster battery on and put a load test on the charging system it falls bellow 11v or fail.

I am assuming its a alternator which took out the battery.

Sigh... Going shopping on Monday for parts.

Thanks again
Peter
__________________
_____________________________
Peter
1999 318ti
_____________________________
318ti is offline   Reply With Quote
Old 09-11-2010, 10:29 PM   #4
318ti
Member
 
318ti's Avatar
 
Join Date: Dec 2004
Location: Toronto Canada
Posts: 61
iTrader: (0)
Default

You know the more I think about this. I think its the regulator (diode) that is leaking and drained the battery. Hence why its draining the battery.

Peter
__________________
_____________________________
Peter
1999 318ti
_____________________________
318ti is offline   Reply With Quote
Old 09-12-2010, 12:38 AM   #5
cooljess76
NOBODY F's with the Jesus
 
cooljess76's Avatar
 
Join Date: Oct 2006
Location: Ventura California
Posts: 7,824
iTrader: (6)
Default

Hey Peter, with the engine running, you should see close to 14v across the battery terminals and at the back of the alternator. I had a bad engine ground and was getting between 10 and 11v. It would fluctuate and slowly build up to 11.7v then drop back down to 10v. In your case, maybe the alternator is bad. You can always take it to your local auto parts store and let them bench test it. They'll be able to tell you right away which part of the alternator is failing. Anyway, hope you get things sorted out soon man. Best of luck, wish I could offer more help.
cooljess76 is offline   Reply With Quote
Old 09-23-2010, 03:36 PM   #6
318ti
Member
 
318ti's Avatar
 
Join Date: Dec 2004
Location: Toronto Canada
Posts: 61
iTrader: (0)
Default Resolved

Thanks to all. Just thought I would add the fix.

The ground was fine, I have double checked them both and all is good.
The voltage on the battery at rest was 12.5v.
With the key out and red battery disconnected, there as 0 amps flowing from the battery + terminal to the cable cable.
With a battery load test, the battery read 1.5v.
When I boosted the car and disconnected the boosting battery, the car stalled.
When I boosted the car and left the battery on the load test on the charging circuit fell bellow acceptable but I would expect that with a bad battery.
The battery is a BMW original about 1.5 years old.
I replaced the battery with a Napa Battery ( 6 year warranty vs BMW's 1 year warranty).
All is well since battery was replaced.

Cheers
__________________
_____________________________
Peter
1999 318ti
_____________________________
318ti is offline   Reply With Quote
Old 09-23-2010, 04:44 PM   #7
cooljess76
NOBODY F's with the Jesus
 
cooljess76's Avatar
 
Join Date: Oct 2006
Location: Ventura California
Posts: 7,824
iTrader: (6)
Default

How much voltage are you getting between the battery terminals when the car is running with the new battery? How about @ the back of the alternator? I ask because when I was having charging system issues, I was getting 10.5-11.7v. 3 batteries and 3 alternators later, I found the REAL problem. Every time I'd replace a battery, it would work fine for about 2-3 months before it would die. I was using Sears Diehard batteries which have a 10 year warranty. You should see 13.5-14v between the terminals when the engine is running. If not, then you've just put a bandaid on the problem and it will certainly haunt you later down the road. If you're not seeing 13.5-14v, I'd highly suggest actually removing both of the grounding cables(negative battery cable and main engine ground located on the passenger motor mount arm) and scrubbing the contacts with a wire brush. Who knows, maybe your old battery was the culprit. But when I visually inspected my grounds, they looked clean and tight. It wasn't until I removed the lower engine ground that I noticed some pitting where the cable must have been arcing because there was no corrosion. Best of luck to ya.
cooljess76 is offline   Reply With Quote
Old 09-27-2010, 03:37 AM   #8
318ti
Member
 
318ti's Avatar
 
Join Date: Dec 2004
Location: Toronto Canada
Posts: 61
iTrader: (0)
Default

With the new battery it was 13.8v I think. I will double check when I get a moment. Likely tomorrow. I do remember checking it, just cant remember. If its light enough I will check at the alternator as well.

I did check the ground(s). They were all good. Clean and solid. Even took a jumper cable and ran it from the battery to a variety of grounds on the car (engine.. etc) Made no difference (as you would expect). Car has been great since the battery was replaced. I will keep an eye on the voltage.

Funny I never think of Sears for a battery. Don't know why.

Thanks
Peter
__________________
_____________________________
Peter
1999 318ti
_____________________________
318ti is offline   Reply With Quote
Reply

Bookmarks


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
charging system help pls! b-rad Electrical 6 09-03-2009 06:27 AM
Charging system issues, electrical gurus your help is needed cooljess76 Electrical 27 02-23-2008 07:56 PM
? about charging my battery zack83 Lounge 4 02-12-2008 04:44 PM
New Battery, but engine still won't start newton318ti Engine 3 12-07-2006 07:11 AM
Is there a fuse for the charging... Tyler Electrical 3 05-15-2006 07:09 PM


All times are GMT +1. The time now is 01:28 PM.


.
Powered by site supporters
vBulletin Version 3.8.8
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Copyright ©1999 - 2024, 318ti.org
© vBadvanced CMPS v3.2.2
[page compression: 89.62 k/105.42 k (14.99%)]

318ti.org does not warrant or assume any legal liability or responsibility for the accuracy, completeness, or usefulness of any information or products discussed.