Battery drain

Mon Jul 24, 2017 4:45 pm

Hi all,
I`ve had a battery drain now since I`ve had the car nearly four years and I have just got around to putting a meter between the earth terminal of the battery and a good body earth.
Now the meter is on 200 ma (? no idea) and is reading @18 things which drops down to 11 things when I remove fuse 21. No other fuse has such a response so have I found the culprit bearing in mind that no bulbs have been in the boot or glove box.

Many thanks Mart.

Mon Jul 24, 2017 6:11 pm

Do you have an alarm and what make is it?

Plus also where do you live and where do you keep the keys

Mon Jul 24, 2017 6:35 pm

If the meter is on the 200mA range, then 18 "things" would be 18mA, which is a low parasitic drain for any E30. Nothing wrong.

Don't know exactly what you mean by no bulb in the glove box, but if the holder is present and it has no bulb in it, then you are risking a short circuit.

Tue Jul 25, 2017 4:59 pm

There are no bulbs currently where they should be which can be rectified.
Is there any thing else I can check to find the drain ?

Cheers Mart.

Tue Jul 25, 2017 8:08 pm

Boot light is fine with no bulb, but the centre contact for the glove box bulb is spring loaded, so with no bulb fitted, it rises up and comes very close to the metallic sides of the holder. So close, it can touch and short out.
If you are measuring 18mA in the negative lead of the battery with everything off, then you do not
have a battery drain - at least, not at the time of measuring.

Tue Jul 25, 2017 8:51 pm

I used one of these to go through all the circuits in the fuse box to see what was drawing a high with the engine off.

Tue Jul 25, 2017 9:55 pm

SexyLady wrote:I used one of these to go through all the circuits in the fuse box to see what was drawing a high with the engine off.

That tool is potentially useful, once you've established that there's an excess current drain by measuring the total current in the battery lead, BUT, if the grand total is 18mA, then you're not going to find any excess current through any of the fuses, just the individual currents that make up the 18mA.

Wed Jul 26, 2017 6:35 pm

[quote="Brianmoooore, but the centre contact for the glove box bulb is spring loaded, so with no bulb fitted, it rises up and comes very close to the metallic sides of the holder. So close, it can touch and short out.
If you are measuring 18mA in the negative lead of the battery with everything off, then you do not
have a battery drain - at least, not at the time of measuring.[/quote]

I have two very good batteries(one was new 3 years ago) and they still goes flat after about 3-4 days.
I would like to nail this in the summer so any help guys ??

Mart.

Wed Jul 26, 2017 6:39 pm

Have you considered the possibility that they are not being charged properly?
What's the voltage across the battery terminals with the engine running at 2000 RPM or so, with the headlamps full on?

Wed Jul 26, 2017 7:30 pm

You can also disconnect the battery for 4 days and see if it dies.

My car also had one of these fitted to it when I bought the so it my have had a battery drain for a while, took me 5 years to get around to sorting it out though, was handy when I got a garage and would leave the car for a week or 2 was just a pain for the ECU to "relearn" and to set the settings for the stereo

https://www.amazon.co.uk/d/Car-Batterie ... B0019ULCPW

Wed Jul 26, 2017 9:16 pm

I have had similar problems with my Cabriolet draining it's battery. Not sure if it's cured it but my alternator drive belt was slightly loose and not charging enough. I want to get a voltmeter, seen some cool ones that fit where one of the dash switches go.

Thu Jul 27, 2017 5:57 pm

If I leave the battery diss-connected for up to 3 months as I have in the past, she would fire straight away (once the gas had got there, Webber).
Four days since I started her and it was instant and before she would have struggled a bit even in the summer.
Brian, the voltage with all lights on at @ 2000 rpm was 13.95v and on tick over without lights was 13.5v, with lights was 12.56v.
I have to use her this weekend as she is in for the test next week early on and I will give her a decent run to sharpen things up a touch but will have to pop the fuse back in so the rev counter works.

Hope this helps in my dilemma ?

Mart.

Thu Jul 27, 2017 9:40 pm

What alarm do you have fitted?

Fri Jul 28, 2017 3:26 pm

Clifford

Mart.

Fri Jul 28, 2017 4:27 pm

martauto wrote:Clifford

Mart.

Lol if you had mentioned that at the start..............

Sun Jul 30, 2017 2:48 pm

SexyLady wrote:
martauto wrote:Clifford

Mart.
Lol if you had mentioned that at the start..............

Thanks but that's not a lot of help.
The batteries both are at 12.4 volts when clap cold and charge OK so is there a way out of this without messing with the alarm?

Mart.

Sun Jul 30, 2017 3:00 pm

I had a Code Alert alarm and had issues for a few years with the battery draining sometimes in 4 or 5 days if the car wasn't used. Last year went through the car and removed all and any components of the alarm.

I can now leave the car for two weeks or a month and it still fires up, go figure.

Mon Jul 31, 2017 8:08 pm

have had the same problem as well , I use a battery master switch on mine if its parked up for a few days solves the problem for me

Wed Aug 02, 2017 4:53 pm

I have a master switch on mine as well and works a treat if left for months but it does not solve the problem.

Mart.

Thu Aug 03, 2017 10:51 am

Do you have a stereo fitted? Maybe that's the cause of the drain...

Could also be duff SI board batteries, or even the clock (if fitted).

Thu Aug 03, 2017 3:53 pm

Its the alarm.

Fri Aug 04, 2017 10:40 am

Your battery is somehwere in the region of 70Ah (it'll probably say on the top)
So a dreain of 18mAh would take a very long time to flatten it, and still several weeks to pull it down to a low enough level to fail to start the car.

Aftermarket alarms do have a reputation of draining things faster than usual but i dont think you's sounds too bad.

Just to confirm, you tested the current drain buy removing the negative battery lead and putting the meter between the negative battery terminal and the lead or a good earth? And thats what gave you the 18mAh figure??

Personally, i'd be looking for a higher charging voltage with the engine running, 12.6v under load is really not enough to be charging the battery. Dont suppose you've got another alternator laying around?

Cheers
Chris

Fri Aug 04, 2017 4:43 pm

Cheers Chris I understand what you are saying and it may not be a bad thing to change it this winter but, I can change the battery and not use the car and it will not last a week without using it.
I have just gone through the test and have left out fuse 21 so I will wait for a few days just to see what will happen.

Cheers Mart.

Fri Aug 04, 2017 6:45 pm

Just very odd that a drain that small is killing it off so quickly.

Bad starter motor pulling too much current?

Sat Aug 05, 2017 2:28 pm

Having just fitted another head unit to my e46 sport, I realised that the head unit on the Baur is permanently live so would this have any bearing on it ?

Mart.

Sat Aug 05, 2017 5:15 pm

Possibly, particularly if its back-up batteries (if fitted) or an electrolytic capacitor are on the way out...

Mon Aug 07, 2017 4:15 pm

Certainly would draw more current, but still 18ma is not a huge amount.

Have you ever checked the battery voltage when it wont start? Just wondering if you may have a weak battery/charging system and a slightly dodgy earth or starter thats asking more than normal. Nothing like a selection of problems clubbing together to make you scratch your head.

Tue Aug 08, 2017 4:58 pm

If it ever stops pissing it down then it`s back to basics Chris, Cheers.

Mart.