Meter settings for checking parasitic draw

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Old 08-18-18, 08:43 AM
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Meter settings for checking parasitic draw

Hi

I am planning to do a parasitic draw test on my car. I have learned from a youtube video that I need to remove the negative/back cable from the car battery & make sure everything possible is turned off in my car before starting the test. I then need to put the red prob from the meter on the removed negative/black cable clamp & put the black prob from the meter on the negative/black battery post. Once all of the above is done, if there is a draw it should show on the meter (over .1 is bad). I then start pulling fuses one by one until the meter number drops to next to zero (the youtuber says under .05). Once I find the offending fuse I can then narrow down the problem to whatever that fuse controls.

My first question is: am I understanding the youtube video correctly?

My second question is: What do I set the dial to on my meter (pic included) & what red port do I use when inserting the red probe plug?

Thanks for any help.

PS: I have no electrical knowledge so please keep it simple if possible lol.

Mod note: Taken from this thread: https://www.doityourself.com/forum/p...r-battery.html
 
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Last edited by dommm56; 08-18-18 at 09:33 AM.
  #2  
Old 08-18-18, 09:59 AM
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Dcv 20..........................................................

DC 10 A

You have DC current in vehicle. AC is for household outlets.
 
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Old 08-18-18, 10:54 AM
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Thanks ukrbyk ...........
 
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Old 08-18-18, 11:04 AM
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He needs to measure DC amps. Start with the switch in the DC 10A position and the red probe in the DC 10 hole (black probe in the COM hole). This position will measure DC current up to 10 amps. If the meter reading is less than 0.2 amps when connected, you can get more sensitivity doing the following. After disconnecting the probes from the circuit, move the switch to the DCA 200m position (this position will measure DC current up to 0.2 amp or 200 milliamp). Move the red probe on the meter from the DC 10A hole to the ma hole. Connect probes to circuit as indicated in your post. Be aware most newer cars always have a current draw with the ignition system in off position (battery current is never zero).
 
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Old 08-18-18, 04:51 PM
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"He needs to measure DC amps. Start with the switch in the DC 10A position and the red probe in the DC 10 hole (black probe in the COM hole). This position will measure DC current up to 10 amps. If the meter reading is less than 0.2 amps when connected, you can get more sensitivity doing the following. After disconnecting the probes from the circuit, move the switch to the DCA 200m position (this position will measure DC current up to 0.2 amp or 200 milliamp). Move the red probe on the meter from the DC 10A hole to the ma hole. Connect probes to circuit as indicated in your post. Be aware most newer cars always have a current draw with the ignition system in off position (battery current is never zero)."

Thanks for your info beelezbob.

I tried both suggestions of yours but I get a zero reading on both your suggestions. From what I understand I should be getting some reading if only small. I checked my meter to make sure the fuse was OK & it is so I'm at a loose on why I'm getting a zero reading? Any ideas?
 
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Old 08-18-18, 06:09 PM
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meter could be bad if you have it hooked up correctly what type of car are you working on?
could also turn on a small dome light or something that will draw a little amperage the light should function and the meter should show amp draw.
 
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Old 08-18-18, 08:34 PM
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Thanks...............................alen73
 
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Old 08-19-18, 02:26 PM
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So here is my update.

I finally got a reading on the meter & I'm figuring the reason I was not getting a reading before was because I was not getting good contact with the probe on the black probe & the negative battery post. I used a plastic clamp to hold the black probe tight to the negative battery post & that seems to have done the trick.

So now for the meter reading. I had the meter dial set to DC10A & the red probe plugged into DC10A. The meter bounced around from .40 up to the .95 range but mostly at the lower end of the above range. The meter only shows for 15 seconds & then it defaults to .0. During that 15 seconds the meter reading never settled, just kept going up & down from the .40 range to an upper end of .95. I could also here the car making strange noises during the test.

So two questions: does the reading make any sense & what was all the noise? Thanks
 
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Old 08-19-18, 02:46 PM
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Those noises were the computers/control modules powering up, resetting and then going to sleep.
 
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Old 08-19-18, 03:02 PM
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Thanks OJmax............any idea if the numbers I posted are within proper range?
 
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Old 08-20-18, 08:12 AM
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If the draw STAYED at .4A I think that would be considered excessive but it's likely the circuits go into a deeper sleep after a longer time than your meter stays awake. When I tested my truck for parasitic loss I found the reading finally took a deep dive to near zero after about 10 minutes. Probably not a coincidence that's the same time period the radio & lights will stay on when you're trying to listen to the radio with the car off.
 
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Old 08-20-18, 10:26 AM
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Update.....I have been told & I agree that my meter is not capable of doing the job I am asking of it. The meter can only take a reading for a continuous 15 seconds & then defaults to zero. I then have to wait 15 minutes before doing another test. Because of those limitations, the meter can not do the job I am asking it to do. Anyway, live & learn & thanks to everyone who tried to help!
 
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Old 08-20-18, 10:43 AM
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Your meter will do what you want but it takes extreme caution.
I'll explain what to do and then it's up to you to do what you want to do.

You'll use the standard probe inputs..... not the 10A input. You will be running the meter in the 200ma range.
Leave one of the meter probes out of the meter. Connect the other two ends like you were previously doing to read current. Use some type of jumper to jump the locations where your probes are. You want the battery connected thru the jumper to the car. Allow 30 seconds to equalize. Plug in probe to meter and remove jumper. Now you are reading the draw very accurately.

DO NOT open the doors or turn anything on in the vehicle. You don't want to exceed the 2A max in this setting.

On edit:
Make sure the interior lights are off before removing the temporary jumper.
 

Last edited by PJmax; 08-20-18 at 06:06 PM.
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Old 08-20-18, 04:47 PM
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2000ua is 2 milliamps. I am sure the ignition off drain is greater than 2 milliamp. Put the switch in the 200ma position when you do the test above.
 
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Old 08-21-18, 07:58 AM
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That range is internally fused at 315mA (not 2A) so proceed with caution if you try the mA ranges. That's not a very common size fuse if you need to replace it.
 
 

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