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Discussion Starter · #1 ·
Does anyone know if this meter will do a dc amp test. I suspect that my truck has a parasitic electrical draw. But I can't seem to figure out how it works. I'm starting to assume now that this meter won't do it. If you think it does please tell me where the dial needs to go to. Thanks
 

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Njuneer
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Says right on it 10A. Pretty much all DMMs will do some DC current BUT you better be checking it for a fuse! The issue you may run into is inrush current when you connect the battery. I do these tests carefully by using a jumper from cable to battery to get it hot, then disconnect that and leave the meter in series to see the current. But in most cases, I just use my DC clamp meter. Those are not nearly as common. Mostly just AC. I use it constantly.
 

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The other problem with using a typical meter like that is sometimes when you pull the fuse and then test the parasitic draw is gone so you'll be running circles. A dc clamp on is the best tool for it since you don't interrupt the circuit.
 

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Discussion Starter · #6 ·
Says right on it 10A. Pretty much all DMMs will do some DC current BUT you better be checking it for a fuse! The issue you may run into is inrush current when you connect the battery. I do these tests carefully by using a jumper from cable to battery to get it hot, then disconnect that and leave the meter in series to see the current. But in most cases, I just use my DC clamp meter. Those are not nearly as common. Mostly just AC. I use it constantly.
Thanks all of you for comments. I know just enough to get into trouble. I have a fluke but it does do amps. I bought this (there cheap) because I wanted to check for amps on certain things. Having issues with my 1995 Ford f 250 so thought I might try checking. I put it to the 10 amps like you said, put my red lead over to the 10 amp red circled receptacle and then detached my ground on the battery. I then put one lead on the neg post and one lead to the neg battery wire and received no readings. So either I have no measurable draw or I'm doing it incorrectly or the new meter is junk. One note, when I hook up the negative lead to my battery there is a small spark so it seems to me that it is drawing some kind of energy. In 1995 there is an obd 1 computer so maybe that is causing the spark but why won't the meter find that. Maybe meter leads are big enough to bridge? If there is another way to check without a clamp on or expensive meter please advise. Thanks guys
 

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Thanks all of you for comments. I know just enough to get into trouble. I have a fluke but it does do amps. I bought this (there cheap) because I wanted to check for amps on certain things. Having issues with my 1995 Ford f 250 so thought I might try checking. I put it to the 10 amps like you said, put my red lead over to the 10 amp red circled receptacle and then detached my ground on the battery. I then put one lead on the neg post and one lead to the neg battery wire and received no readings. So either I have no measurable draw or I'm doing it incorrectly or the new meter is junk. One note, when I hook up the negative lead to my battery there is a small spark so it seems to me that it is drawing some kind of energy. In 1995 there is an obd 1 computer so maybe that is causing the spark but why won't the meter find that. Maybe meter leads are big enough to bridge? If there is another way to check without a clamp on or expensive meter please advise. Thanks guys
LOL, you possibly just popped the exact fuse I warned you about! When you first put a battery cable on, it lights up the computers, charging up capacitors, and current draw can get high for a moment, which is exactly why I mentioned the jumper technique.

Now you need to see if the meter has a fuse and if you blew it. For meter, one lead on the 10A term, other on common (middle)0 term. Measure in series between batt post and cable end. See if meter is blown first, then we can move forward.
 

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Discussion Starter · #8 ·
Well the meter itself turns on and is working, I'll also senses voltage and continuity. I opened it up and there's two fuses one says 200 ma I'm assuming is milliamp, and one is a 10 amp. They're solid covered fuses so you can't see that they're bad but I cannot get continuity through it so I'm assuming that those fuses are now bad. They're not even dark. I believe I tried this before this time so I probably kill them a long time ago. So what I don't understand is your jump wire. So let me ask you this, is what you're saying is I should remove the negative from my battery, install a jump wire, wait for a while and then touch the two probes? Which I believe should be in series. Sounds like I want to just see what the draw may be but after the truck is powered up some things. But why even remove the cable at all? Obviously, I'm not understanding something.
 

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Well the meter itself turns on and is working, I'll also senses voltage and continuity. I opened it up and there's two fuses one says 200 ma I'm assuming is milliamp, and one is a 10 amp. They're solid covered fuses so you can't see that they're bad but I cannot get continuity through it so I'm assuming that those fuses are now bad. They're not even dark. I believe I tried this before this time so I probably kill them a long time ago. So what I don't understand is your jump wire. So let me ask you this, is what you're saying is I should remove the negative from my battery, install a jump wire, wait for a while and then touch the two probes? Which I believe should be in series. Sounds like I want to just see what the draw may be but after the truck is powered up some things. But why even remove the cable at all? Obviously, I'm not understanding something.
Your type of meter MUST be in 'series' between the battery post and cable to see what current is going through it. The jumper method is a PITA, but it works if we need a sensitive read. You disconnect the ground cable, then jumper between the cable and post for, oh, 5sec or so. BEFORE you disconnect the jumper, you have your meter leads connected between the post and cable, so when you remove the jumper, the meter maintains connection between the post and cable. I use clamps for the leads. Work smarter, not harder.

All this is doing is letting the jumper take the inrush loads of capacitors and such. The inrush can be well over 10A.

With only the meter on there, you ARE limited to 10A or it blows. you open the truck door, you are probably screwed.

There are other ways to do this. One being a test light between cable and post. however, that is an archaic method. When you have a DC clamp meter, you use it..... I am pretty damn accurate down to about 100mA!

You will likely find those fuses are 'very fast blow' fuses, so a little harder to find but you DO want to get the right ones. installing standard fast blows is asking for meter death.

You may not be aware, but ECMs have different modes of 'sleep'. Very normal to see them pulling a full amp sometimes, and then they start to sleep over several minutes. I think we see them get into sleep modes at 5min or so. So it is critical that you leave the meter on for a period of time to see if the ECM sleeps. If you have several amps, there is probably something else going on. I caught a stuck seat switch by seeing a cycle between like 100ma to 5A or more every few seconds. That would NOT be an ECM typically.
 

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Njuneer
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Search for 10A meter fuses on Amazon. Check the physical dimensions of yours to make sure you order the right one.

View attachment 706272
(y)(y)(y)(y)THANK YOU!!!!!

Pictures are SO much easier.....

FORGOT to mention that if when you first connect the battery, all the cab lights turn on, headlights, etc, do NOT remove the jumper until all that stuff as shut off. It might take more than 5sec. Use common sense.
 

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Discussion Starter · #13 ·
Yeah okay I get it. I did find the fuses online and ordered some and they are fast fuses. So I know about the car doors, lights, radio whatever you can think of so I didn't have any of those on in fact there's even a light in the hood which I unplugged. I'm not informed of the term "PITA" but I can look that up. On the jumper wire what gauge should I be looking at? So I'll hook up the jumper wire, get everything to power up the capacitors and then put my meter on and pull the jumpers. I presume since I've loaded up the capacitors it won't try to load them up again and blow the fuse. Also, if I have some kind of big parasitic draw I suppose it could go over the 10 amps and blow the fuse again. Doesn't sound like a very good way to test. I do have a test light, and obviously that doesn't have a fuse or at least I don't think it does. Even though it's hillbilly testing I can use that? Worst case I just blow the light bulb I guess or ruin that tester which is what I've been trained to do. LOL viper, I appreciate the handholding.
 

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Yeah okay I get it. I did find the fuses online and ordered some and they are fast fuses. So I know about the car doors, lights, radio whatever you can think of so I didn't have any of those on in fact there's even a light in the hood which I unplugged. I'm not informed of the term "PITA" but I can look that up. On the jumper wire what gauge should I be looking at? So I'll hook up the jumper wire, get everything to power up the capacitors and then put my meter on and pull the jumpers. I presume since I've loaded up the capacitors it won't try to load them up again and blow the fuse. Also, if I have some kind of big parasitic draw I suppose it could go over the 10 amps and blow the fuse again. Doesn't sound like a very good way to test. I do have a test light, and obviously that doesn't have a fuse or at least I don't think it does. Even though it's hillbilly testing I can use that? Worst case I just blow the light bulb I guess or ruin that tester which is what I've been trained to do. LOL viper, I appreciate the handholding.
If you had a parasitic draw on the order of 10A, your battery would be dead in day or less.

Typical parasitic draw is around 30 to 50 mA these days. It's probably less with older cars /trucks with fewer electronics that need power all the time.
 

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Yeah okay I get it. I did find the fuses online and ordered some and they are fast fuses. So I know about the car doors, lights, radio whatever you can think of so I didn't have any of those on in fact there's even a light in the hood which I unplugged. I'm not informed of the term "PITA" but I can look that up. On the jumper wire what gauge should I be looking at? So I'll hook up the jumper wire, get everything to power up the capacitors and then put my meter on and pull the jumpers. I presume since I've loaded up the capacitors it won't try to load them up again and blow the fuse. Also, if I have some kind of big parasitic draw I suppose it could go over the 10 amps and blow the fuse again. Doesn't sound like a very good way to test. I do have a test light, and obviously that doesn't have a fuse or at least I don't think it does. Even though it's hillbilly testing I can use that? Worst case I just blow the light bulb I guess or ruin that tester which is what I've been trained to do. LOL viper, I appreciate the handholding.
If you have a power draw that exceeds 10A, I bet you would know it quick because your battery won't hold that very long at all. Like over night, dead to the world.

You cannot blow a test light! because they is the secrete in a resistive bulb element. At least at 12V. They automatically current limit. We use them to limit current to test electronics!

put it to you this way, connect a test light lead clamp to neg, then probe the pos on the batt. What happens? Bulb turns on....lol

As for jumper, hell, I have used 18ga wire in a pinch. If you want a spec, I would say 14ga anything or better. Speaker wire, whatev. You will see sparks, that is things powering up. Then it will get sleepy real fast.

I'd love to design/build a real draw tester for this but cheap asses will never buy it....lol I will stick to NASA work...
 

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Discussion Starter · #16 ·
Okay, thanks for clarification. Seems to be about 3 weeks then low battery. I have quite a few vehicles and a couple of boats and I've noticed that the batteries aren't holding up to as in the past. I'm using interstate batteries so I think I'm buying a quality battery.
Thanks again for you help.
 

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Many mechanics chased it, as did I over multiple weekends. It was intermittent, but I found it. The ignition switch.

Would have been money ahead if I'd bought a new van right at the start.
 

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Okay, thanks for clarification. Seems to be about 3 weeks then low battery. I have quite a few vehicles and a couple of boats and I've noticed that the batteries aren't holding up to as in the past. I'm using interstate batteries so I think I'm buying a quality battery.
Thanks again for you help.
First thing to do is disconnect the battery and see what happens! very few people understand that 12.7V is full charge, and 12.0 is pretty much dead! If a battery loses that much charge in a few weeks, it is bad!

Other problem I see is over charging....like a LOT! Floated safe voltage is about 13.8V. Very fine to run at 14.7 or so for topping, but if a battery lives there in a hot vehicle? yeah, you gunna roast it! Boils the electrolyte right out of it.
 

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Discussion Starter · #19 ·
First thing to do is disconnect the battery and see what happens! very few people understand that 12.7V is full charge, and 12.0 is pretty much dead! If a battery loses that much charge in a few weeks, it is bad!

Other problem I see is over charging....like a LOT! Floated safe voltage is about 13.8V. Very fine to run at 14.7 or so for topping, but if a battery lives there in a hot vehicle? yeah, you gunna roast it! Boils the electrolyte right out of it.
The first thing is I really don't charge to many battery's because I use them a lot and the vehicle usually has plenty of amps. I do take care of my batteries (Clean them, check water when possible, add distilled water) We did a little test with some new batteries on a load tester and two of them came out fair at best. This is one of those little toaster over type testers.

I have an 11 year old Sears diehard that still test ok voltage wise and a one year old interstate that does not. When I went online you could still buy an american made battery, made from NEW lead instead of recycled that spec. really well. Drawback?, $300 something bucks. They made it sound like our recycled Chinese batteries are junk....I tend to believe them.
 

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If you constantly need to add water to batteries, you have an overcharge issue! I've seen many $xxxx burned up with charging practices. Learn about batteries and it might save you some coin. really matters none how 'clean' your batteries are, or even if you add water. If you are not monitoring the charge voltage, you are probably screwing yourself and not even knowing it.
 
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