Battery Drain??
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From: Tn
Battery Drain?? 4-8-19 Update/ problem solved
Hello all,
1975 model coupe, I thought I had a parasitic drain, I left a new battery connected for an hour or so and it was too weak to crank the car. Installed a cutoff on the Neg. post, use it religiously, no more problems.
I decided to try to locate the problem, got a new multimeter, testing for amperage draw from the Neg. post to the Neg. cable. On the 10A setting, doors closed, I show "0"?? On the mA setting, doors closed I show .84??
I really don't know where to go from here, I think some small amount of draw is normal? But how much? Perhaps I don't have a drain after all? Or it's intermittent? Thanks in advance for your thoughts and advice,
alton9
1975 model coupe, I thought I had a parasitic drain, I left a new battery connected for an hour or so and it was too weak to crank the car. Installed a cutoff on the Neg. post, use it religiously, no more problems.
I decided to try to locate the problem, got a new multimeter, testing for amperage draw from the Neg. post to the Neg. cable. On the 10A setting, doors closed, I show "0"?? On the mA setting, doors closed I show .84??
I really don't know where to go from here, I think some small amount of draw is normal? But how much? Perhaps I don't have a drain after all? Or it's intermittent? Thanks in advance for your thoughts and advice,
alton9
Last edited by Alton9; Apr 9, 2019 at 05:53 PM. Reason: Update
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My battery drain was the center rear glove box. It was leaving the light on even when closed. All I had to do was bend the mount a little to shut it off. Might check that.
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From: Tn
I followed the instructions in the link posted above, test light lights with door open, does not with doors closed, according to that, I don't have a parasitic drain? But I do show a .84mA draw on my multimeter...... I just don't know if that is a normal or an acceptable amount?
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with the Ammeter attached, start methodically removing fuses until the current draw stops. You will know what circuit has the parasitic draw. Then you can start to determine what device is doing it and correct as necessary.
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From: Tn
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From: Tn
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From: Lake in the Hills IL
Then someone pointed that out to me Saturday and I put my red lead into the other hole for mA and set my multimeter at 200 mA. Which confirmed 140 milliamps.
My guess is you are getting 840 milliamps of draw then. That is a problem. Be careful though so you don't blow a fuse with the draw as there are usually 2 fuses with different ratings depending on the type of test. I blew a fuse at one point being a dummy/not knowing how to use the multimeter and the fast blow/ceramic little dinky fuses aren't cheap.
Show us a picture of the multimeter with how you have it set and the reading you are getting. Also take a look at my post from the other day. I had a lesser draw, but same process is followed.
Last edited by raydog9379; Aug 24, 2017 at 03:56 PM.
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From: Tn
Which hole is the red lead plugged into? Reason I say this, is that I was doing it incorrectly as well and had it plugged into the 10a hole and then mA recorded .14. Basically I was getting 140 milliamps.
Then someone pointed that out to me Saturday and I put my red lead into the other hole for mA and set my multimeter at 200 mA. Which confirmed 140 milliamps.
My guess is you are getting 840 milliamps of draw then. That is a problem. Be careful though so you don't blow a fuse with the draw as there are usually 2 fuses with different ratings depending on the type of test. I blew a fuse at one point being a dummy/not knowing how to use the multimeter and the fast blow/ceramic little dinky fuses aren't cheap.
Show us a picture of the multimeter with how you have it set and the reading you are getting. Also take a look at my post from the other day. I had a lesser draw, but same process is followed.
Then someone pointed that out to me Saturday and I put my red lead into the other hole for mA and set my multimeter at 200 mA. Which confirmed 140 milliamps.
My guess is you are getting 840 milliamps of draw then. That is a problem. Be careful though so you don't blow a fuse with the draw as there are usually 2 fuses with different ratings depending on the type of test. I blew a fuse at one point being a dummy/not knowing how to use the multimeter and the fast blow/ceramic little dinky fuses aren't cheap.
Show us a picture of the multimeter with how you have it set and the reading you are getting. Also take a look at my post from the other day. I had a lesser draw, but same process is followed.
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From: Tn
Ok, apparently I don't know how to post pics. My meter dial is set to mA, the red lead is plugged into the 500mA max plug, not the 10A max plug. DC current is selected with the button that toggles between AC and DC. The reading on the screen is 0.84. When I checked using the 10A settings, I got "0".
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From: Lake in the Hills IL
Ok, apparently I don't know how to post pics. My meter dial is set to mA, the red lead is plugged into the 500mA max plug, not the 10A max plug. DC current is selected with the button that toggles between AC and DC. The reading on the screen is 0.84. When I checked using the 10A settings, I got "0".
Thread Starter
Intermediate
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From: Tn
Ok, apparently I don't know how to post pics. My meter dial is set to mA, the red lead is plugged into the 500mA max plug, not the 10A max plug. DC current is selected with the button that toggles between AC and DC. The reading on the screen is 0.84. When I checked using the 10A settings, I got "0".
Figured it out!!!!!!! The posting pictures part anyway.......... The leads didn't show up in the pic, but for mA I'm plugged in on the right hand side, for 10A I plug in on the left hand side. The black lead plugs in the middle.
Last edited by Alton9; Aug 24, 2017 at 04:52 PM.
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Leaving your multimeter set where you have it on (mA)...turn on your headlights and post what it reads.
The turn them of and open your door and post what it reads.
The see what it reads when you turn it to the 10amp setting on your tool.
The way I am reading this. 0.84 mA is almost an amp.
When I check the Corvettes I check...I am looking for my tool to show .100 or .200 on the screen. If it gets to .300...begin to have concerns
DUB
The turn them of and open your door and post what it reads.
The see what it reads when you turn it to the 10amp setting on your tool.
The way I am reading this. 0.84 mA is almost an amp.
When I check the Corvettes I check...I am looking for my tool to show .100 or .200 on the screen. If it gets to .300...begin to have concerns
DUB
Thread Starter
Intermediate
Joined: Aug 2017
Posts: 44
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From: Tn
Leaving your multimeter set where you have it on (mA)...turn on your headlights and post what it reads.
The turn them of and open your door and post what it reads.
The see what it reads when you turn it to the 10amp setting on your tool.
The way I am reading this. 0.84 mA is almost an amp.
When I check the Corvettes I check...I am looking for my tool to show .100 or .200 on the screen. If it gets to .300...begin to have concerns
DUB
The turn them of and open your door and post what it reads.
The see what it reads when you turn it to the 10amp setting on your tool.
The way I am reading this. 0.84 mA is almost an amp.
When I check the Corvettes I check...I am looking for my tool to show .100 or .200 on the screen. If it gets to .300...begin to have concerns
DUB
door open set to 10A reads 1.982
door closed, headlights on, set to mA reads 3.22
door closed, headlights on, set to 10A reads 0.00 I think I may have blown a fuse in my new meter.....now I get no reading of any kind on 10A