Meter reading help

[marinaman]

Hi all

Trying to still find the slow drain, decent weather so at it all day yesterday.

Im stuck with my multimeterm after reading the excellent post from X5 Sport on how to trace i connected up withe the meter acting as the earth return,
i set the meter to DCA and on the 20a setting.
When with door open and the system still awake it reads 0.15,  after the 16 mins it goes to 0.06
i was pulling fuses to see if the figure changed but nothing did. few times i woke the system by fuse pulling and the dvd in the boot spun up and the reading went to 2.35 for few mins then slowy dropped eventually back to sleep at 0.06.
The reading shown on the photo 4.40 that was with some circuits activated,  so does that read as  4.4 amps ?
if that is 60ma  then that seems a good overnight draw and normal ish, this has only happened since the cold weather in November,  been fine from when battery was new in March 2017  95 amp Bosch S4

Can someone tell me how to read this. is 0.15 equal to 150ma  and 0.06 equal to 60ma ? or 6a ,  4.40 equals 4.4 amps
had battery load tested at garage and he said it was fine but still get small daily drain that would flatten car after around 10 to 14 days if not used.
Thankyou

[X5Sport]

Correct.  60mA isn’t bad for the sleep cycle.  Most new cars in dealerships need recharging at least monthly, more often for the latest or more fancy models.

I have left my X5 at the airport car park for a couple of weeks before and all has been fine - until the starter went TITSUP (Total Inability To Support Usual Performance).

[marinaman]

Hi
Thanks for that  but why then would a mere 60ma over such a short time flatten it,  its a 95amp battery

Just come back from garage afte taking other car,  i asked the chap there on reading meter  he says different to you    hope dont start arguement      he said the 0.06  was actually  6 full amps    that would account for 6 amps a night over say 10 nights equals a drop of 60 amps from the 95 total i have.

in that case  whats the meter in the photo showing a 4.40

does that sound right or wrong,  think i may just buy a self ranging meter for £13 on Amazon,  that should then stop the confusion should it ?    this meter shown is set on 20a dca setting
Startin to pull what bit of hair i have left out  :blink: :blink:  So  if i get 0.06 when car not used is that 60ma  or 6a

[X5Sport]

0.06 on a 20A scale selected is 60mA.  6A would be 6.00  The 20A range is likely to be the most that meter can handle without blowing a fuse.  I can’t actually read the selected scale on your meter as the image resolution is too low.

A 6A current draw would flatten the battery overnight.  All current ratings are in Amperes per hour (Ah).  If the battery is a 95Ah battery, then 6A (correctly written as 6Ah) will kill it in less than 16 hours, though it is likely to be a little quicker than that due to the battery chemistry.

Methinks your technician can’t read a meter.  The ‘4.40’ reading would be 440A on his scale, and that is twice what the starter draws and would kill the battery in less than 15 minutes (not to mention probably boil it!)

[marinaman]

Had it on the 20A DCA scale    the other scales are 2A then  220m, 20m, 2m and 20u  sadly not an expert in meters  will have to read up

so if 0.06 is indeed 60ma    then the 4.40 on the 20a scale is 4.40ah    thats the reading that came up when a circuit or two were energised after pulling fuses and putting back in,    then the reading settled down to 1.14  then 0.06
so it appears then that if the reading 60ma is acceptable then i didnt notice it as the year went on as the battery held up much better in the warmer weather,  but this has been a winter thing  draining much faster

Does this all sound correct,  if so i can put it to bed and stop hunting for a drain that isnt there
whats the code for the actual biggest battery you can fit.  i have the Bosch 95a 800cc 013 part number  but apparantly that is an 019 in the UK    i see they do a slightly larger 100a  doesnt seem a lot though 5a bigger

[X5Sport]

Bosch S4 013 is a ‘019’ format battery.  The 019 is the battery dimension code used by all manufacturers for that shape battery with those terminals.

Cold weather will always find a ‘weak’ battery as the chemistry slows down.  I can’t remember what the actual BMW spec says, but given you have the alarm and central locking ‘listening’ for your key, 60mA sounds fine.

[marinaman]

THANKS for all your help X5  :beer2:

[sleepyfolk]

I know your battery is only a year old but it wouldn’t be the first battery to fail in a short space of time, when it was manufactured and how it was stored play a big part before it gets to you.
Where did you buy it? Somewhere that might not quibble with a return hopefully!

Be careful with the so called battery testing as well, doing a quick drop test in Halfords with their rubbish doesn’t often prove a lot other than it can supply enough current to spin the car over in a short space of time. It would be interesting to see it bench tested with a measured load at the 20 hour rate and see how it held up over a longer period but I accept that’s likely not possible. I’ve got a Bosch S5 019 in mine - as you say not a lot bigger capacity to make a big difference.

[marinaman]

see what you mean, i took the battery to my local garage who put it on a drop tester, said it was fine,  then i took it to the shop where i bought it and he did same test and said it was fine.
I  suppose i would have to insist at the shop it was sent away for proper testing if they would do it, i think they get their batts from Andrew Page, so how they would test it i dont know, probly same drop test,  they then may say,,  its fine,  where do you go from there,  a never ending circle,

As it is its sitting overnight and i pop out and look and its showing a same 0.06 on the meter over many checks so i guess its just lack of use on our part and hope now the winter is over it will hold up longer.
Will just have to pop it on the ctek maybe once a week to keep it topped up.

[marinaman]

so  bought this meter only £12  said self ranging

instructions as per most far east a little hard to interprit and just shows a few diagrams, didnt want to spend a fortune on something little used but they could describe how its supposed to self range

why has it got selectors then on the dial for V , and A and others if its self ranging , getting a bit more confused

any help gratefully accepted    Thanks
just been googling, says to use the 10a if above,  or m A  if lower    but not above 250ma    so if i use that range and the car wakes up its going to put more than 250ma through 

[sleepyfolk]

Not sure what to suggest really, my drain was cured by changing the heater FSR, I also changed the starter motor which also might have been drawing too much current and straining an already old battery, then changed the battery and all ok since, although I’m too much of a scaredy cat to leave it for 10 or 14 days without starting it to be honest!
Form memory when I was reading up before on it I’ve seen mention of anything from 30Ma to 60Ma as normal when it’s asleep so I don’t know who’s right, seems that a few folk have found spurious issues where body/Bluetooth/nav modules woke up for no apparent reason causing current draws of 4A on and off, but they only found this by having a oscilloscope that records connected overnight or for 48 hours in the garage - again not an easy option to test for unless you’ve got a friendly auto elec/Bosch centre nearby willing to park it in a corner of the workshop for a night or two!
It’s not terribly easy to test what current your starter motor is drawing yourself,  you need a fairly pricey ammeter but if you can find somewhere local it would be interesting to know so you could eliminate it, likewise I guess you’ve checked your voltage when the cars running to indicate the alternator is giving a good charging voltage?

[marinaman]

My final readings were 0.06 which i understand from X5Sport is 60mA which is correct drain
as weather now milder i am expecting the car to drain slower, its been over the last few months of very low temps that this has shown itself,
i think i will now go down the route of charging every 10 days with the ctek while the car is not used rather than letting it flatten right down which i gather isnt good for them.
Seems i bought a self ranging meter and expected a miracle but not to be. I have seen now some very very expensive ones that are actually just that, turn on and they know what you are measuring without selecting anything on any dial,  for the pro .
Will have to study meters and electric theory more online i think.

[X5Sport]

To help you.....

From the left side ‘Off’ the meanings are:
Voltage DC - for cars etc
Voltage AC - domestic mains supply is ac.
Resistance (Ohms)
Diode check with tone (diodes only conduct voltage in one direction so this tells which end is +ve)
Capacitance (in Farads at a guess if autoranging but could be milli/micro or nano (mF/uF/nF)
Frequency (in cycles/sec or Hertz)
Current DC/AC in micro Amps 0.000001 = 1 uA
Current DC/AC in milli Amps 0.001= 1mA
Current DC/AC in Amps
Off

The three connectors are Centre = Ground/Negative; Left = is for currents up to 10A before the fuse blows; Right = is for all other measurements and current up to 250mA (0.25A) before the fuse blows.  Black lead goes into COM and Red (+ve) lead into to relevant Red ringed socket.

[A Blair]

I was following your thread.
The multi meter is correct. I am thinking you possibly have a bad connection. 60mA is nothing. 12 x.06 = 0.72 watt / hour. This is nothing. The battery test sounded good, specially as you had a second opinion.
The bad connection would stop your battery being charged correctly when running. So in the morning you think you have a drain, but the drain occurred running the car. A hot engine starts easier so you need to let it cool before starting again.
Have you tried measuring the voltage on the battery terminals (not the connectors) when the car is running. What does it say. If there is a bad connection it will also have more resistance and cause the terminals to be warm.
Check and clean the battery terminals and connectors.
Apply a little vaseline to stop them oxidising.

I use a clamp meter (its called the hall effect) to measure how much charging current the battery is receiving. This might be key in the diagnosis. See if you can hire one.
Lets know how you get on.

[marinaman]

Hi
Yes , have done running volts check on battery direct etc, all tight and looking as new and coated with petroleum jelly.
The Ctek battery sense does show that when the car is started the charging voltage rises so i think all is ok on that front as i get good readings from the alternator under load.
The drop is when its stood for many days but it seems as small as 60ma is,  its enough over a few weeks to deplete the battery.
i think now its just been a cold winter syndrome and things will improve as it was around a month of no use last summer that ran the battery down, which again i understand is normal ish.
Thanks for all help.