Technical Battery Draining

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Technical Battery Draining

Joined
Apr 24, 2005
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145
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Location
Cumbria
For the second time in about 4 months my stilo has had a flat battery. On both occassions the AA have come out and restarted it, and on both occassions on measuring the drain on the battery they have found something taking about 3.6v from the battery. The patrols have then proceeded to see if its something obvious, e.g. glovebox light stuck on etc and found nothing. Usually during this time the drain reduces to about 0.3v. They have suggested taking it to the dealer, but they claim there is nothing wrong.

On this last occasion, after restarting the car the "engine fault" light was displayed. Therefore, on the advice of the AA patrol I took it immediately to my dealer with him in tow (excuse the pun). Typically upon restarting the engine for the dealer the car passed all its checks and didn't display the engine fault light. I just don't know whether to trust it now.

Also, has anyone else experienced mystery battery drainage, or have any suggestions as to what could be causing it? The only thing I do know is that on both occasions the car had not been used on the previous day (i'm sure its just a coincidence though)

Cheers
 
How old is the battery? Have you had all the battery cells checked out ok?
A dud cell can discharge as fast as the charge goes in and will give you similar symptoms. Low battery voltage also provokes warning systems to trigger.

Not quite with you when you say something is draining 3.6v. You can have a current drain ie Amps but a battery only producing 9volts would be time for the bin
 
Hi,

On 3 separate occasions my battery has done the same. Once while on Holiday for 2 weeks, once when I didn't use the car for 1 week and once after only 3 days. It actually has little to do with how long I left it.....

If I had been listening to the CD Changer and not switched back to radio before turning the ignition off it seems that the CD player keeps running and flattens the battery. The music never carries on from where I left it, it's always tracks or CD's ahead. (interesting feature, it's always a surprise)

Took me a while to work it out. But on each occasion I had been using the CD changer before switching off the engine and coming back to flat battery.

Quality!!!!
 
On both occasions the AA have tested the battery using their laptop system and reported thats its in "great condition" I would guess the battery is 3 years old.

On the subject of the drainage amount, the AA say the car is drawing 3.6 and a typical reading should be in the range 0.1-0.6. I don't know what unit its measured in, but I presumed it was Volts? On both occassions the drawing of power has dropped to 0.1 which is a "really healthy" reading.
 
mbarratt2 said:
AA have tested the battery using their laptop system and reported thats its in "great condition"
These types of test don't hold for a possible intermittant problem such as shorting plates. :(

I'd put a new battery in.
 
A 3 year old battery is getting on a bit and if it let me down once I wouldn't let it do it again.

0.1 amp is acceptable residual battery drain current. 3.6amp? Well if you have a 50amphour battery you can work out it wont take long to die.

A dud cell can charge up and make the battery look good but then lose all its charge erratically

I'd stick a new battery in too
 
Thanks everyone, I felt the battery age may be a contributary factor, but I was reassured by the AA patrol that there was no such thing as a battery lifespan. I just hope its nothing more serious with the cars electrical system.

Has anyone any advice on which brands of battery to buy and where to go for one (i.e. buy one at Halfords or visit your dealer for one)
 
Batteries can last for ages depending on how battery is used; Left idle or only doing short trips are a killer. Most recommend a heavy duty battery equivilent to reduce problems of low volts start up triggering warning systems. Other than that you pays your money.....
 
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Gonna bring this one up and ask a new question . . .

Our 1.6; still plagued with Electronic Power Steering Faults, but the array of ABS/ASR/EBD faults are back too. We put in a new (Alfa) battery last summer, and all calmed down but is back again - car left my parents without steering today!

Checked the car today when they got back, and the battery cell is showing a very dark green, almost black. This usually means low battery, but they went out to a town 30 miles away for the afternoon, and then came back - car had no starting issues.

Ideas? We're stumped. We kept the battery we took out and trickle charged it, it's remained green for months. Might swap it with mine but no doubt the 1.6 will run it low again!!
 
Well, as you know Rich, if the start up battery voltage is low then those warnings will trigger. It's not something wrong or a fault in the car, it's quite rightly saying that the voltage in those systems isn't right. Sensitive little bugger i know but it does it's job just right, the way it's been programmed to do. It wasn't told to ignore low voltage at start up and so doesn't know any different. If they go away after starting or on second start then that's the Stilo way.

If the voltage won't get high enough then you're not allowed power steering. Very choosy about voltage

Black indicator isn't good, I'd check the voltages before start, during cranking, when running and after left idle for a few hours. Check for a battery drain if it's going down. Might have a cell gone or poor charging or a constant drain. Have to find out which

I take it you don't have persons playing music or playng with the goodies with engine switched off?
 
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Gonna bring this one up and ask a new question . . .

Our 1.6; still plagued with Electronic Power Steering Faults, but the array of ABS/ASR/EBD faults are back too. We put in a new (Alfa) battery last summer, and all calmed down but is back again - car left my parents without steering today!

Checked the car today when they got back, and the battery cell is showing a very dark green, almost black. This usually means low battery, but they went out to a town 30 miles away for the afternoon, and then came back - car had no starting issues.

Ideas? We're stumped. We kept the battery we took out and trickle charged it, it's remained green for months. Might swap it with mine but no doubt the 1.6 will run it low again!!

Earth cable.
 
Decks, how do I check voltage drain? And no, nobody listens to music in the car without engine.

T, "Earth Cable" - elaborate please :)
 
As T1 says, a bad battery earth can cause charging and power supply problems. Check the earth contact where it connects to the engine. If you don't want to get your hands dirty, check the voltage drop on the earth line. Put one end of your multimeter on a good engine earth (not the earth lead itself) and the other lead on battery terminal going to earth, set the multimeter to read 1 volts and under range then crank the starter and see what voltage drop you get. Should be quite low = around 0.5volts or less. Any more than that and you have a bad earth

Current drain is what we mean by battery drain not voltage. Should be very little current drain when everything is switched off. So with everything switched off, disconnect a battery lead and stick your multimeter in between to complete the circuit then measure the current flow which should be quite small as there'll still be a few things on like alarms etc
 
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Check the voltage drop like i said and that will point you to a bad earth connection if you have one. Clean the connection at the earth lead to engine connection and (i doubt you'll have problems here) but check the lead for disintegration.

Could check your alterantor output while you're there
Check voltage across battery with no load >14v
Full load, headlights, hrw etc hi tickover >13.25v
 
Nice job for tomorrow :)

What do you think T means by "earth cable"? Take it off and clean it? Or replace it?

Between body & engine is often suspect(can give error warnings,poor charging/starting)...need to remove battery tray to do this though.Remove sheathing from a section of the earth cable(especially at gearbox terminal),any signs of black on cable then renew (£15).
 
Between body & engine is often suspect(can give error warnings,poor charging/starting)...need to remove battery tray to do this though.Remove sheathing from a section of the earth cable(especially at gearbox terminal),any signs of black on cable then renew (£15).

Thanks T, shall go playing tomorrow :D

Just to confirm - we're only talking about the negative terminal battery wire here?
 
Ok cool. Shall remove the cable in the morning, the car's not going anywhere for a few days. Taking the battery box out should be fun - I had a joyous time with it on mine :p
 
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