Battery current draw when sitting?
Thread Starter
Melting Slicks
Joined: May 2000
Posts: 2,148
Likes: 1
From: Chandler AZ
Battery current draw when sitting?
Anyone else measured the total amps drawn from the battery with everything OFF- ignition, lights, etc?
I'm seeing .5 amp which seems high; no wonder the battery is always dead if you don't drive it. Should anything else be on besides the anti-theft? I'm going to pull a few fuses and see if I can pin it down better.
I'm seeing .5 amp which seems high; no wonder the battery is always dead if you don't drive it. Should anything else be on besides the anti-theft? I'm going to pull a few fuses and see if I can pin it down better.
Team Owner
Joined: Aug 2000
Posts: 40,156
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From: San Pedro CA
Re: Battery current draw when sitting? (gcrouse)
there was a tech artical on this a few months ago in one of the mags... I will try and track it down...
If I remember correctly, the normal no-load drain should be about .25 amps.
If I remember correctly, the normal no-load drain should be about .25 amps.
Team Owner
Joined: Dec 1999
Posts: 34,873
Likes: 487
From: Lacey WA RVN 68-69
NCM Sinkhole Donor
Re: Battery current draw when sitting? (gcrouse)
Check the underhood lamps. Pull the fuse and check draw again. Also the glovebox and center console lights.
IF you have the C68 Electronic Climate Control, it helps a little to hit the OFF button before shutting the engine down.
IF you have the C68 Electronic Climate Control, it helps a little to hit the OFF button before shutting the engine down.
Team Owner
Joined: Mar 1999
Posts: 89,144
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From: Life's tough, wear a helmet.
Re: Battery current draw when sitting? (gcrouse)
If you've got any aftermarket stuff (cell phone, stereo) hooked up check that out, too. There was a cell phone installed in mine when I bought it and after 5 days of sitting it wouldn't start. I uninstalled it as soon as I discovered that was the problem.
PS: I also don't go 5 days without driving it anymore either!
PS: I also don't go 5 days without driving it anymore either!
Drifting
Joined: Jul 2001
Posts: 1,477
Likes: 0
Re: Battery current draw when sitting? (jfb)
all of the above. the ECM does drain constantly on all cars but shouldn't be a high amount.
Heard a group of mechanics debate that one until they did a test in the shop.
someone lost an expensive dinner. :lol:
Heard a group of mechanics debate that one until they did a test in the shop.
someone lost an expensive dinner. :lol:
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Thread Starter
Melting Slicks
Joined: May 2000
Posts: 2,148
Likes: 1
From: Chandler AZ
Re: Battery current draw when sitting? (gcrouse)
Thanks for the ideas so far guys; to answer a couple questions:
No lights on at all; even pulled the "Courtesy" fuse.
I'm measuring with a digital meter directly in series with the battery.
As far as I can tell, the only things that should draw current are the Theft system, radio clock, and ECM.
I've also noticed some noises when re-connecting the battery that sound like the headlight control unit is doing something (also initial current draw of >5amps).
No lights on at all; even pulled the "Courtesy" fuse.
I'm measuring with a digital meter directly in series with the battery.
As far as I can tell, the only things that should draw current are the Theft system, radio clock, and ECM.
I've also noticed some noises when re-connecting the battery that sound like the headlight control unit is doing something (also initial current draw of >5amps).
Le Mans Master
Joined: Nov 2000
Posts: 7,391
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From: Chandler AZ
Re: Battery current draw when sitting? (gcrouse)
FYI... my battery would die after a week of sitting...Security light would not quit flashing after motor is off even with doors closed. Turned out to be the Theft Detterant Module. No more dead batteries:)
Drifting
Joined: Mar 2001
Posts: 1,636
Likes: 3
From: Lafayette IN
Re: Battery current draw when sitting? (gcrouse)
If all other checks fail (don't forget to pull the breakers near the fuses), you might end up tracing it down to the starter or the alternator. Remember, these aren't directly fused, so pulling fuses ignores them. -Matt-
Team Owner
Joined: Mar 1999
Posts: 22,025
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From: At the beach in little Rhody
Re: Battery current draw when sitting? (HighHopes85)
First, make sure the key is out. If it is in, the CCM will go into "wake-up" mode. The current draw on my 90 (from memory, don't have manual anymore) was 15-19 milliamps (0.015-0.019 amps) in the manual. If you have a Lojack, it will be about 8 to 10 milliamps higher. 1/2 amp is WAY too much. You have a short somewhere. I had a short once after bleeding the brakes because we bled the brakes too fast, but a few pumps of the pedal solved the problem. Go through your breakers pulling them one at a time to find out what circuit is the culprit.
