Battery Drain

[Guest gooner52]

quick update on mine

 

just been out to check the volts no drop (yes a bloody last)was 12.65 still 12.65

 

even seems to be put`in more volts when charging

 

so from this i would say my old battery woz nafted

[big_kev]

They seen you coming with that heavy duty battery.....

 

How long did that last then ?

[Andrew T]

National Tyres agreed to replace my battery under warranty but when they couldn't source the correct size they've fitted a Diesel sized one f.o.c. The correct size always looked pitifully small for the size of engine it has to turn over, it's hardly any bigger than the one on my 1.5 Honda. The speed it turns over now undelines how knackered the other battery was, and all that spare capacity won't go amiss.

[Guest gooner52]

old battery was on from july 05...

[Guest greenfingers]

Big Kev, where is 'relay 109' located? I haven't tried any relays yet.

I imagine that if it were draining a significant amount, it would probably be warm to touch?

Could this be a clue......I'm getting excited now! Need some daylight time, will report back this weekend.

[RADIOTWO]

Big Kev, where is 'relay 109' located? I haven't tried any relays yet.

I imagine that if it were draining a significant amount, it would probably be warm to touch?

Could this be a clue......I'm getting excited now! Need some daylight time, will report back this weekend.

 

Greenfingers

 

You have not said how long you run the car for each day?

 

Radiotwo

[tim-spam]

And you still do not have the correct battery fitted....

[Guest greenfingers]

You have not said how long you run the car for each day?

 

Actually, the car often only does about 5 miles around town in a day. However, it also occasionally does 100 miles in a day. I do realise that it doesn't always get fully charged every day, but the same goes for my van, which has done this for 5 years on the same battery.

 

I would be very interested to hear if anyone other than Big Kev has had a relay causing the battery to go flat. I am planning to delve behind the fusebox into levels 2 and 3 this weekend, and any tips on what to look for would be appreciated.

[Smilge]

Just a bit of reference stuff I looked up:

 

Self Discharge:

 

Batteries discharge themselves continually, even when no loads are attached. At room temperature, a modern low-antimony battery will lose about 0.1 .... 0.2% of its total charge each day. As the battery ages, antinomy transfer to the negative plate, combined with other sources of contamination can increase the rate to as much as 1% per day. This ultimately leads to battery failure.

Rule of Thumb for the influence of temperature: The rate of discharge doubles with every 10 degree C increase in temperature. The self discharge rate of lead calcium batteries is only one fifth as high, and it also remains constant throughout the batteries life.

 

Maintenance:

 

The only correct way to check the charge of a battery is to check the specific gravity of the electrolyte;

 

The battery should be charged whenever the figures drop below 1.20 g/ml or 12.2V. Low-maintenance and maintenance free batteries are best recharged using the UI mathod and a maximum voltage of 14.4V. This method allows adequate charging times on the order of 24 hours - without any risk of overcharging.

 

UI Method of charging

 

Because the standard charger is non regulated the charge current will drop steadily due to their internal resistance and because they dont control the charging voltage, they are not optimal for charging maintenance free batteries.

 

You need to provide a constant charge current to protect the charger until gassing commences and then revert to a constant charge voltage to protect the battery against overload.

 

Well hope this helped a litttle and also hope that you sort this problem soon matey ..threads getting too big. :wacko:

 

Good Luck

 

Chris

[Guest gooner52]

update on my battery

 

as you know i was losing around 0.50 volts a day

 

have since had new battery fitted and i am not losing anything

 

checked last night 12.54 and today in between 12.54 and 12.53

 

so it would seem my problem was defo the battery

[Guest greenfingers]

Good show Gooner, bet you feel more confident when you turn the key on a cold morning now.

Wish mine was that simple.

[Guest gooner52]

yes m8 i do..

 

but i know what your going through..

 

made we wonder if she would start .all the time before

hope you get yours sorted m8 :16:

[Guest greenfingers]

This thread is loo long - and it's been boring me for ages.

 

Needs someone to pull the rabbit out of the hat!

 

Anyone got an original idea?

 

Tomorrow is gonna be D-Day. :16:

[big_kev]

It wasn't the relay causing the battery to go flat it was the bodeged temporary repair job that I did that caused it to go flat.

 

p.s. I still think your alternator is knackered

 

Have you found a battery that will hold a charge over a few days yet ?

[Guest greenfingers]

Nope, all batteries die on this car.

[big_kev]

There you go knackered alternator

[Guest wolfie]

I'm going towards the duff alternator theory as well! IIRC doide failure in some cases will allow a charge voltage to be produced but will allow the battery to discharge through the alternator! I could be wrong though? but it's

[Guest greenfingers]

I'm going towards the duff alternator theory as well! IIRC doide failure in some cases will allow a charge voltage to ......

 

OK, this is going over old ground again, but what the hell, I'll try anything.

It is 9.50pm, and I have just gone outside and disconnected the main alternator lead and the 2 wire connector.

The car was run for well over an hour today, so I believe the battery has recharged fully.

In fact, it has been standing for over 4 hours now, and I have just read 12.73 volts with everything switched off.

 

I will report back tomorrow ( D-day ;) )

[Guest greenfingers]

Oh, and nice graphics Big Kev, but I meant in a metaphysical kinda way! ;)

[Shabazmo]

Just received February edition of Car Mechanics magazine and on page 55 it shows a current tester that you plug in the fuse slot after removing the fuse. It ca be bought from www.testtools.co.uk for

[NikpV]

looks useful ......

 

:huh:

[RADIOTWO]

Just received February edition of Car Mechanics magazine and on page 55 it shows a current tester that you plug in the fuse slot after removing the fuse. It ca be bought from www.testtools.co.uk for

[NikpV]

looking at the picture - no - but even if it didn't a mini fuse + standard fuse holder 2 bits of wire and 10 mins with a soldering iron would knock up an adapter :huh:

 

what would worry me would be this scenario - 5A fuse blows and you plug this in and reads 17A - what damage would you be doing ?? I suspect its only really useful for investigating leaking circuits although a modified standard fuse connected to a normal multimeter would do the job as well - maybe not as useful as I thought after all

[Shabazmo]

Reading more in Car Mechanics who are doing a project on a Mk1 Sharan. They too had a problem of a new battery going flat in 2 days and suspected a battery drain. They used a clamp meter put around the earth cable from the battery and connected the cb100 clamp meter which can measure down to 1mA. 0.001A. they said "we quickly identified 5mA of current still seeping through enough to drain a battery after a couple of days". They then disconnected each fuse in turn and when the current fell to 1mA they knew that was the problem. It turned out to be the radio which someone has wired a permanant feed instead of ignition feed thus illuminating the radio all the time. Hope this helps.

[Guest greenfingers]

looks useful ......

 

:)

 

 

I don't see that it offers any real advantages over a standard ammeter - I've just tested every circuit in the fusebox by bridging the fuse contacts with the two probes.

 

Incidentally, my battery dropped the usual amount last night with the alternator disconnected. :lol:

As I just said, I've been out and tested every circuit in the fusebox. The only currents (apart from interior lights) that I found with ignition off were:- No 30 (stereo) .11A, No 32 (central and engine electrics) .08A, No 8 (12V sockets) .01A.

These add up to total the resting current of .2A which I have measured again at the battery.

 

I had hoped to be able to identify any circuits with a constant feed, and then remove their relays. However, after looking at the various relays in level 2, and referring to TIS to see what they do, I have confess to being out of my depth and unable to make sense of it all. :(

 

Alas, the time has come to end the suffering. :o

 

Today is D-day! :lol:

 

I have been speaking to a nice sounding bloke from Yorkshire. He wants a Sharan. Even when I explained this elusive problem to him, he was not deterred. He is making the three hour journey down here tomorrow. :wacko:

 

So my dear friends, this may signal the end of our short but very enlightening relationship. These cars are special -great space, versatility, fuel economy, plus good looks and handling: but I have learned very quickly that you need to be fully dedicated and prepared to lavish them with constant attention. :lol:

 

This forum is one of the best resources I have ever discovered. Tribute should be paid to the dilligence and kind-hearted help that so many members contribute. Testament to this is how some ex-Galaxy owners can't seem to leave. Maybe I will be one of them! :lol:

 

Anyway, the decision has been made....blub, blub....Thanks to all of you who have helped me through this misery.....I will give you all an update on the outcome tomorrow - tomorrow is Release day ! ....maybe. :lol: