View Full Version : Key-off current draw
MaXJohnson
February 12th, 2005, 09:09
does anyone know how much current is flowing out of the battery when the key is off? I know the ecu and stereo suck a little to maintain memory, but I'm showing around 1 amp when I pull the positive battery cable off and put a digital VOM between the cable and battery post.
My Jeep just barely cranks over, very labored. The system shows around 14 volts when it's running and the battery, a two year old red top tests good. I'm suspecting it's just a bad starter, but I'm surprised by the current reading.
cheers
XJJPR
February 12th, 2005, 09:14
I have such a big draw it kills the battery when it sits for 3 days, and it is a good battery! I'm right now disconnecting it until I can find the problem. My situation sucks because I have cut so much stuff out HALFWAY I need to go back and rewire the whole thing just for the stuff that is left.
1 amp seems high for normal stuff!
hinkley
Lou
February 12th, 2005, 09:20
One(1) Amp is too high.
An easy way to isolate the excessive draw problem is to systematically pull/replaced fuses(Main panel) until the excessive draw is eliminated.
From there, you have isolated the branch/circuit that is causing the problem--move to the interior sub-panel to further isolate it.
MaXJohnson
February 12th, 2005, 09:21
I pulled all the fuses out of the panel and removed the starter cable and wire at the solenoid. Still flowing 1 amp. Where the underhood relays are mounted on the passenger side, the smaller battery positive lead goes to a binding post and feeds four wires. Two of these show the 1 amp drain, but I don't kow where they all go. I'm guessing the binding post is on the starter relay?
gjxj
February 12th, 2005, 09:31
one thing to watch -- when electroninic devices start up they pull
extra current, so when you do the check be sure to wait a minute
or so for a correct reading.
1 amp is too much even considering that though. I'd expect
to see 100ma initially then it should settle down to ~10ma.
badge714
February 12th, 2005, 09:57
Don't know if this helps but i had a draw on son's 97xj turned out to be underhood light shorted out. just a thought badge 714
Eagle
February 12th, 2005, 10:00
MaX --
You have an older XJ, correct? The post you are referring to is on a rectangular metal "cannister"? If so, yes, that's the starter relay. Try just unscrewing that and separating it from the body. It may have an internal short to ground.
MaXJohnson
February 12th, 2005, 11:20
yup, mines a '90. Thanks for the info, Eagle. Ill try that.
Looking at my cheepo Haynes manual, it looks like some of those wires go to the alternator. I'm on my third alternator. Mud seems to do them in and I was in some pretty gooey stuff just before I started having the electrical problems.
I keep telling myself to put the rubber mud guard back under the front end...
MaXJohnson
February 12th, 2005, 12:06
well, just finished putting on a rebuilt starter and that took care of the starting problem. Still have the current draw, but at least it's running again. :)
Now I'm just like Hinkley
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