Post Reply 
Thread Rating:
  • 0 Votes - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5
2010 Chevy Cobalt LT Battery
12-28-2013, 12:40 AM
Post: #1
Exclamation 2010 Chevy Cobalt LT Battery
I bought a used 2010 Chevy Cobalt LT (20, 500 miles) last year and have been experiencing problems with the battery intermittently dying. I have tried replacing the battery. A voltmeter revealed that there is a current draw on the battery even when the car and all accessories are completely shut off. I narrowed the draw to the 50 amp inline fuse in the 10 gauge wire in the trunk, although I wasn’t able to successfully trace it. Where does the wire go and what should I check in order to discover the cause of the problem?
Find all posts by this user
Quote this message in a reply
12-28-2013, 01:21 AM
Post: #2
RE: 2010 Chevy Cobalt LT Battery
Having never worked on a Cobalt I guess we're going to need you to do a bit more investigation. If you are not sure what the #10 wire feeds then what doesn't work when you pull the fuse? Does the car have rear load leveling shocks? How about a serious stereo and that's the amp feed? I wouldn't imagine a car of that size has a tow package with an extra feed to the rear so I am looking for hints.

Oh, you didn't say how long it takes to go dead or exactly what the draw is but I suspect you already checked for things like a bad alternator and the trunk light. Still having trouble grasping what other items might be in the rear that would require a #10 wire, presuming that's from the factory. If it's not factory then I would disconnect it in the front and see what happens. The fuse should be as close to the battery as possible anyway.... and a 50 amp fuse is too big for a #10 wire if it's an after thought.
Find all posts by this user
Quote this message in a reply
12-28-2013, 12:06 PM
Post: #3
RE: 2010 Chevy Cobalt LT Battery
I don’t know about a 2010 Cobalt but the 2009 has the battery in the trunk. That could explain some heavy wires including ones that will lead back up to the alternator.

Please let us know what you find as it could help others.

Thanks for using the forum,

Interested in Mining? Look here: Coal Mining, PA
Visit this user's website Find all posts by this user
Quote this message in a reply
12-28-2013, 02:46 PM (This post was last modified: 12-28-2013 03:37 PM by SLF206.)
Post: #4
RE: 2010 Chevy Cobalt LT Battery
Thank you for your comments so far. Here is some of the additional information you requested:

When the battery is being drained (as it only seems to be happening intermittently) the battery will drop to around 10V after the car has been off for 24 hours.

The wiring is original and the battery is in the trunk. The wire leads to the front of the car and doesn't feed anything in the back directly. Also the car does not have rear-load leveling shocks, a serious stereo or any after-factory equipment. With the car running, the car immediately quits when the fuse is pulled. Also, when the fuse is pulled there is no clicking from the starter when the key is turned in the ignition.

Measured the current draw through the suspect wire with no key in the ignition and nothing on. Current started at 2.0 amps and dropped suddenly to 600 ma then to 300 ma after 2 minutes. Trunk light was on after fuse inserted, but nothing else was turned on. Then measured resistance from non-battery side of fuse holder. Resistance started at 1.6 K ohms. Then after 2 minutes resistance went up to 34 K ohms. 300 ma does not sound out of the ordinary, however I am thinking that when the battery gets drained the current draw never drops from the initial 2 amps. Any suggestions?

Is it possible that the wire is the feed coming back from the alternator?
Find all posts by this user
Quote this message in a reply
12-28-2013, 05:40 PM
Post: #5
RE: 2010 Chevy Cobalt LT Battery
Almost sounds as if the fuse might feed a whole bunch of things but a #10 wire with a 50 amp fuse is too small for the alternator output and way to large for just the ignition, fuel pump or ECM.

A 2 amp draw is about right for the BCM feed to the interior lights, radio, and other things on that delay after the key is turned off.

Is there anything listed in the owner's manual for that fuse?
Find all posts by this user
Quote this message in a reply
Post Reply 

Forum Jump:

User(s) browsing this thread: 1 Guest(s)