Battery drain and Multimeter not reading

[greenlawnjeeper]

I have a battery drain and have tried bridging the battery posts/cables with my meter and haven't gotten any readings. I tried the bridge with first the negative side and then the positive side - and gotten the same result. I used the 10A scale. I'm not any sort of electronic guru so maybe I have the meter switched to the wrong scale? Should I use the scale above the 10A. I figured with a dead battery resulting from a week sitting (this happened "out of the blue"), it would be at least 1A registering. Help please .

ps. I should have gotten some kind of reading because I attached the under hood light but what I don't understand is that the light, didn't light when I did the bridge test. It did light when I connect the battery cables . Apparently current is not flowing thru the meter?

Sorry for the slightly blurry photo.

 

[hubs97xj]

First thing I see is that you don't have the leads connected properly. See the empty socket with "10A" on it?

 

[winterbeater]

x2. Maybe when the dial is on a GREY section, the red cable should be in the GREY hole, and when on a RED section it should be in the RED hole. Most likely your battery is too old and won't hold the charge long enough any more. But clean all your cables and grounds first anyway. And keep testing.

 

[greenlawnjeeper]

x2. Maybe when the dial is on a GREY section, the red cable should be in the GREY hole, and when on a RED section it should be in the RED hole. Most likely your battery is too old and won't hold the charge long enough any more. But clean all your cables and grounds first anyway. And keep testing.

Thanks guys for your quick replies. I did try the black wire in the 10A slot and still got no reading. The battery is new. I put it in 2 weeks ago, then it sat for a week while I worked on a radiator replacement, went to start it to purge the radiator - and the battery was dead. Now I guess I could have gotten a bum battery but in the meantime, I've charged it up to 13+ volts (via a battery tender) and wanted to check for a drain before I merrily went on my way (and end up with another dead battery). I will look for the multimeter instructions and recheck those connections. Again, many thanks.

 

[playwithit]

If you want to read amperage, you will need the meter to be in series. Hook one lead to the battery post, one to the battery cable.

 

[hubs97xj]

Measuring DC current with a Craftsman 82141 DMM (never underestimate how useful Google can be when working on your junk).

DC CURRENT MEASUREMENTS
CAUTION: Do not make current measurements on the 10A scale for
longer than 30 seconds. Exceeding 30 seconds may cause damage to
the meter and/or the test leads.
1. Insert the black test lead banana plug into the
negative (COM) jack.
2. For current measurements up to 200mA DC, set the
function switch to the 200mA DC position and insert
the red test lead banana plug into the (mA) jack.
3. For current measurements up to 10A DC, set the
function switch to the 10A range and insert the red
test lead banana plug into the (10A) jack.
4. Remove power from the circuit under test, then open
up the circuit at the point where you wish to measure
current.
5. Touch the black test probe tip to the negative side of the circuit.
Touch the red test probe tip to the positive side of the circuit.
6. Apply power to the circuit.
7. Read the current in the display. The display will indicate the proper
decimal point and value.

 

[winterbeater]

Thanks guys for your quick replies. I did try the black wire in the 10A slot and still got no reading. The battery is new. I put it in 2 weeks ago, then it sat for a week while I worked on a radiator replacement, went to start it to purge the radiator - and the battery was dead. Now I guess I could have gotten a bum battery but in the meantime, I've charged it up to 13+ volts (via a battery tender) and wanted to check for a drain before I merrily went on my way (and end up with another dead battery). I will look for the multimeter instructions and recheck those connections. Again, many thanks.

RED wire in 10A slot. Keep black wire in black slot.

 

[greenlawnjeeper]

RED wire in 10A slot. Keep black wire in black slot.

You're a man of few words - yup, that was my problem. Now (finally), I think I know how to work the Multimeter. Many thanks to all.

Fred

 

[greenlawnjeeper]

Measuring DC current with a Craftsman 82141 DMM (never underestimate how useful Google can be when working on your junk).

DC CURRENT MEASUREMENTS
CAUTION: Do not make current measurements on the 10A scale for
longer than 30 seconds. Exceeding 30 seconds may cause damage to
the meter and/or the test leads.
1. Insert the black test lead banana plug into the
negative (COM) jack.
2. For current measurements up to 200mA DC, set the
function switch to the 200mA DC position and insert
the red test lead banana plug into the (mA) jack.
3. For current measurements up to 10A DC, set the
function switch to the 10A range and insert the red
test lead banana plug into the (10A) jack.
4. Remove power from the circuit under test, then open
up the circuit at the point where you wish to measure
current.
5. Touch the black test probe tip to the negative side of the circuit.
Touch the red test probe tip to the positive side of the circuit.
6. Apply power to the circuit.
7. Read the current in the display. The display will indicate the proper
decimal point and value.

I think the instructions that I had were written in Chinese, translated badly to English, back into Ebonics to Chinese and then (badly) into English again. Yours are much better.
Thanks

 

[Jeepsloth]

I hooked mine (Fluke) between the negative post of the battery and the connector on the cable, and set the meter to milliamps. If it is 20 or 25 milliamps like mine was something is draining the battery. Start pulling fuses until the drain goes away, then you'll know which circuit has the problem. Or you could use a test light the same way, when the light goes off you've found the circuit.

 

[greenlawnjeeper]

Now that I found out how to use the multimeter, last night set on the 10A scale, with the underhood courtesy light connected, I get a reading of a 1.02 draw. I disconnect the bulb and get a zero reading. Moving the red wire from the 10A slot to the mA slot, I also get a zero reading. What I don't understand is why when I connect the underhood courtesy light, and do the bridge test on the mA reading, the light doesn't light up (like it did when I did the test on the 10A scale

The reading last night after full charge with the Battery Tender was 13.3 volts. The reading this morning after sitting overnight (30 degrees) with the Tender disconnected was 12.94 volts. Is that to be expected? Car started fine this morning and was reading +14 volts when running.

I'm assuming now that I don't have a parasitic draw and will head back to Cosco for a replacement battery if I get slow cranking again or (obviously) if it goes dead again. Thanks all for UR help.

ps. FWIW, the battery in my S10 Blazer, which is a Cosco that sat in my wife's Camaro for 7 years, that replaced the dead Exide in the Blazer last year (so it's now an 8 YO battery), read 12.6 volts this morning and it doesn't sit on a tender. It always starts on the first crank so I assume you wouldn't want less than say a 12.5 volt reading on a sitting battery.

 

[hubs97xj]

When you moved the red lead back to the socket on the right, did you set the meter to the mA scale, or leave it on 10A?

Also, since you know the light draws more than 1A, take the bulb out when using the mA scale. You don't need to add more variables here, and your meter may not like getting hooked up incorrectly and juiced all the time.

 

[greenlawnjeeper]

When you moved the red lead back to the socket on the right, did you set the meter to the mA scale, or leave it on 10A?

Switched to the mA scale.

What "happens" then if the draw is 1A (or more) and you're using the mA scale?

 

[hubs97xj]

Ideally it just blows a fuse, but I don't know the specifics of your meter, or whether it incorporates some other sort of protection.

If the underhood light is the only draw, and it wasn't on during the time the Jeep sat parked, I'd be inclined to think you have a bad battery- at this point, I'd hit an auto electric shop or a parts store, and have them test the battery.

 

[Jeepsloth]

Disconnect the connector from the light and try the test, you have to recreate a situation where everything is off then check the mA draw at the negative side of the battery.

 

[greenlawnjeeper]

Disconnect the connector from the light and try the test, you have to recreate a situation where everything is off then check the mA draw at the negative side of the battery.

Thanks - did that - reads zero. I guess there is no parasitic draw. I'm thinking battery at this point (even though it only 2 weeks old). Might just bring it back to Cosco for a replacement. Autozone (for a test) isn't really easy to get to. But a test would answer any questions.

 

[Shorty]

The reading last night after full charge with the Battery Tender was 13.3 volts. The reading this morning after sitting overnight (30 degrees) with the Tender disconnected was 12.94 volts. Is that to be expected? Car started fine this morning and was reading +14 volts when running.

a fully charged, at rest 12V battery should stabilize at 12.65V (given enough time to bleed off the excess surface charge) Your results are exactly what you should expect to see.

I'd be inclined to think you have a bad battery- at this point, I'd hit an auto electric shop or a parts store, and have them test the battery.

I'm not sure I follow your rational, but a load test is always a good idea after a discharge and recharge cycle. Just be sure it's fully charged when it's tested or they can damage the batteries plates from the excessive heat generated with low voltage available.

 

[greenlawnjeeper]

Thanks - I'll then monitor the situation and verify the reading doesn't go below 12.65 V.

 

[Shorty]

I too, would just keep an eye on it-- not sure why the battery drained with a week of sitting (is it still the same battery, or did you replace it) but try one night, then two, the three and monitor the charge each A.M. If it's good to go after each, chalk it up to a mystery.

 

[hubs97xj]

My rationale is simply that good, new, batteries do not fully discharge themselves in a week. We just have to assume there's not a simpler explanation (like leaving a light on, and of course assuming he's testing draw correctly, which he seems to be), but for someone who's not terribly familiar with auto electrical systems, a free 2 minute system test seems like a reasonable suggestion.