No reading when trying to check parasitic drain with multimeter. Help!

Bad Sir Culation

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Evening all.

I thought I knew what I was doing with the multimeter, but the damn thing is saying 0 to everything when I try to test for battery drain.

Followed this guide to the letter:
How to Find a Parasitic Battery Drain: 9 Steps (with Pictures)

I believe that I need the multimeter dial set to the big A on the right hand side, is that correct?

20140108 213845

If that's the case, then why on earth does it say 00.0 or 0.00 etc. when it DOES drain the battery if left overnight??
 
Just checking the obvious, but you had the test leads in the bottom 2 sockets and the meter in series with the battery negative?
 
Yep. Checked it can read the battery voltage etc. OK too so that I can rule out anything being dead.

It's bizarre.

Tried the 10A setting bottom right too. I then put the battery lead back on, read the voltage and watched it flicker, 12.05, 12.04, 12.03 so there must be SOMETHING going on, but unfortunately it looks like I a never ever going to get to the bottom of it.

I got a Vag Com scan done the other day, and there were three entries, N75 short to ground - intermittent, Lock/Unlock switch; interior short to ground and Tailgate Open Switch short to ground. These are basically all I have to go on now I think.

Most of these codes are from before I had the car, so the next time I get it read may shed a bit more light.
 
Meter should be on 10A or 200m, any less than that and you may damage it.

Odd it's not reading at all, maybe try and borrow another meter?
 
Right, black probe in the "COM" port. Red probe in the top "10ADC" port.
Turn the dial so that it is in the 10A position.
Disconnect the battery earth.
Put red probe on the earth cable. Black probe on negative terminal of the negative battery terminal.
Check for a reading.

Is that exactly the method you followed?
 
you are using 10A switch setting and plugged in accordingly yes? and using it "in series" with either the +ve or -ve battery lead yea?
 
How do you know your battery is good?

It would be quite a drain to drop the voltage as quickly as you suggest.

Get the battery checked or swapped out is what I'd do.
 
hi

funny stuff electricity, just won't stay where you put it :)

assuming the meter was connected in series, if you used the bottom two terminals, and any of the lower amp setting on the dial, ie the next segment clockwise from V~, you probaly blew the inernal fuse, as this part of the meter can only hande 200ma, whcih is way less than the initial surge when connecting the battery.

to measure on the higher range, you need to use the top and bottom terminal, com and 10ADC and set the dial to 10A

If you did connect using the lower range there is a chance that the fuse did not protect the meter, it is possible for it to measure volts but the amps section to be dead

good luck
 
Yes to Badger5. Tooks, the battery will still have 12v if left disconnected for a week, so no issues there.

Best check that fuse then. What sort of fuse is inside one of these meters?
 
Yes to Badger5. Tooks, the battery will still have 12v if left disconnected for a week, so no issues there.

Best check that fuse then. What sort of fuse is inside one of these meters?

Battery voltage is no guarantee of a batteries health.

There will always be a drain on the battery when parked up, but not enough to cause a healthy battery problems.

What are the symptoms that lead you to think something is draining the battery? Is it flat come the morning? Is it lazy to start?

Have you checked the health of the earth points, particularly the one on the engine block? Are you getting a healthy 14+ Volts from the alternator? I understand the car is newish to you? Is the alternator the right amp rating? All this can gradually wear a battery down/kill it.

Apologies if you've checked all this, or I'm teaching you to suck eggs, but faulty batteries are common. My wife had a car with all sorts of weird stuff going on, wipers self activating, sometimes dead, sometimes firing up first time, and a new battery cured it.

Good luck finding it anyway, electrical problems are indeed maddening!
 
Battery voltage is no guarantee of a batteries health.

There will always be a drain on the battery when parked up, but not enough to cause a healthy battery problems.

What are the symptoms that lead you to think something is draining the battery? Is it flat come the morning? Is it lazy to start?

Have you checked the health of the earth points, particularly the one on the engine block? Are you getting a healthy 14+ Volts from the alternator? I understand the car is newish to you? Is the alternator the right amp rating? All this can gradually wear a battery down/kill it.

Apologies if you've checked all this, or I'm teaching you to suck eggs, but faulty batteries are common. My wife had a car with all sorts of weird stuff going on, wipers self activating, sometimes dead, sometimes firing up first time, and a new battery cured it.

Good luck finding it anyway, electrical problems are indeed maddening!

No it's fine, any help is appreciated. Alternator I thought was fine as testing battery voltage while the engine is running shows 14+v. Am I wide of the mark in thinking that's proof of alternator health? Not sure how I check it is the correct rating?

Reason I know the battery is draining is because if I leave it connected overnight, it is dead the next morning. Tries to start if you're lucky and quickly dies completely. Multimeter shows something like 5 or 6v at this point usually.
 
from the manual

To continue protection against fire, replace fuse only with the specified
voltage and current ratings: F 250mA/250V (Fast Blown) Ø 5 x 20

http://www.histest.com/blog/files/2012/02/Sinometer-DT830B-Digital-Multimeter-Users-Manual.pdf


no fuse on the 10A circuit, if thats not reading correctly the meter may be dead :(

do you know anyone that can check it?
m

Strange! The meter is literally a month old. I DO have another somewhere that needs a battery in.... if I can find it!
 
what was the first connection you made? if it was using the lower range you could well have damaged the meter, despite having a fuse, they don't call electronics "fuse protection devices" for nothing :), i've blown more meters than people have turbos!

i'm about an hour south of leeds, just of M1/M42, if you're passing anytme i can have a poke around with the meter

"No it's fine, any help is appreciated. Alternator I thought was fine as testing battery voltage while the engine is running shows 14+v. Am I wide of the mark in thinking that's proof of alternator health? Not sure how I check it is the correct rating" This shows its charging ok, but not that it may have a reverse drain when you switch off.
 
I have made some progress this evening. I found my old multimeter which worked a charm.

The drain was generally sat around 2.5 to 3 amps, with the odd spike here and there when messing about with fuses.

The end result of tonight was that pulling the fuses, both at the end of the dash and in the battery top fuse box, made no difference to the drain.

What am I to make of that? I know my hazard switch is faulty and needs replacing, but even if this was to blame, wouldn't one of the fuses also be for the hazards and thus cut the circuit when pulled?
 
could be the alternator (probable) or starter motor(low probability), both are connected direct to battrey via bolted fusible links, so no fuse in fuse box

you would need to unbolt the connections, i recall them being on top of the battery

good luck
 
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Dude, I can guarantee you (well almost) its the black cable going to the alternator in your fusebox on the battery thats going to be causing the drain.

Put the multimeter on there and you should probably see about a 2.5amp drain.

Mine did the same and it ended up being a diode in the alternator that was causing the issue. Replaced the alternator and all ok now.
 
Result!!

Well, it's only the ****** alternator. Great! But at least now the mystery is solved. Thanks very much to all that have helped me with this, it's really got me over the line.

:applaus:

Edit: I did also want to ask another question. If I leave the radio knob popped out in the ON position, the radio comes on when I am testing the circuit in series. I don't need to worry about the radio draining the battery whenever I leave it like that do I? It doesn't stay on or anything when the car is shut off. Just weird it comes on when I am testing.
 
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As my son says...toldja!! LOL

I had the same headache trying to work the issue out too.

Not too sure about the radio issue though.

Glad you are getting it sorted.