Battery dying

Spacecowboy

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For the 2nd time in a month my S3 has failed to start due to drained battery. The first time I was in a field and had the stereo on for 3 hours straight so no surprises.

Second time was this morning. I had left the car standing from Tuesday morning till Friday - got in and it wouldnt start. RAC out this morning to jump it with a power pack. It is the original battery to the car.

Few questions:

1) When it was started first time it went flat, the independent Green Flag chap put a clamp onto the fuse pack on top of battery - is this okay?
2 The ABS light has come on once since (last week). I was told this morning this is due to the battery being crap. Could this also be linked with the way it was started last time as he did put it to the ABS fuse strip?
3) How can I check it is the battery and not the alternator knackered or both?

There was a thread on here a couple of weeks back where someone picked up a battery for a good price. Done a search and cant find it. Anyone got any tips of where to go? Not paying £100 plus in dealer prices.
 
Did the Green Flag man remove the clamp? Are you sure it was a clamp and not an ammeter? He may have been checking the current flow to the battery to assess the alternator. Take the car to a garage or decent parts shop like GSF and they'll test the battery.
 
Sorry, I wasnt clear. Green Flag had a boost Power Pack (as opposed to starting it off another car) to get it going. He put one lead clamp on the battery (right side) and the other end of - I think the minus lead - on the fuse pack on top of the battery to start it. He didnt use a voltmeter or ammeter to check the battery strength - he just started it.

Would this type of practice damage the ABS in any way as it was the fuse strip he put it to and hence the light or is the light indicative of a knackered battery as per the RAC guy's advice this morning?

Would Halfrauds be able to check the state of the battery and/or alternator for me? At a cost most likely...
 
Okay, found place selling Exide batteries for S3 @ £44 all in. Good brand? Good price? Seems cheap.
 
Or Global with 3 Yr warranty for £44.65 all in. Any preference with you'se guys?
 
I picked up a Bosch Silver Bat for my S3 a few months ago from a local EuroCarParts. I think it cost between £45-50.
 
I suppose first thing is to check all the lights are off when you turn the car off, including the boot light if you have one?
 
Yep no probs there. I know nothing about batteries - I'm sure they are all the same at the end of the day?
 
Bosch Silvertop for me too. Very cheap if you have access to Costco. I would doubt the RAC man has damaged anything by connecting the Negative to the fuses on the top of the battery. He could have also used any part of exposed metal under the bonnet if he wanted.
 
Daft question: have you checked the fuse for ABS to see if it blew?
 
Yes, fuse no prob. He reckoned it was just down to the battery that it lit up the other week. It was the Green Flag guy who did the weird jump start - RAC bloke this morn was ex VAG technician so I'll go with his explanation. Just wanted to run it past the multitude first. Cheers Y'all.

PS - what makes the Bosch battery better than the others?
 
colinra said:
Bosch Silvertop for me too. Very cheap if you have access to Costco... He could have also used any part of exposed metal under the bonnet if he wanted.

What is Costco?

And you are right about hooking lead up to any metalic engine block part - it is reccomended in the manual. Its just finding a piece!:faint:
 
To test whether it is the battery or alternator you need a voltmeter, you can pick up a cheap digital one from most car shops.
Start by testing the voltage across the battery with the engine off it should be reading roughly around 12v, it may still read this if the battery was recently charged i.e. if you've just driven it, but if knackered will drop considerably over the course of a few hours.
Next test the voltage again this time with the engine running, if it reads the same as before the alternator may be knackered, ideally it should be reading within the region of 14v with the engine on tick-over.
I had the same problem with my S3 turned out to be the battery, replaced it and all was fine.
Sorry it's a bit long-winded but hope this helps.
 
It does help. Halfrauds did a test on just the battery at standstill and it read 12.5v but as you say i had just driven it. i saw a thread on here yesterday (but cant find it now) saying that if the revs increase on startup its the ECU compensating for somewthing (cant remember what) which basically means that something is knackered - but cant remember what! It does this on mine for a couple of mins on start up...
 
Spacecowboy said:
i saw a thread on here yesterday (but cant find it now) saying that if the revs increase on startup its the ECU compensating for somewthing (cant remember what) which basically means that something is knackered - but cant remember what! It does this on mine for a couple of mins on start up...

I missed this thread aswell.... my S3 on start up revs high for a few minutes and then settles, did anyone have an answer to this ? or the link to the thread ? :icon_thumright:
 
Dubplate are you sure yours isnt the choke? Mine starts at over 1k RPM then drops to around 750 - 850 once its warmed up. My car was doing this all the time after I got it out of the garage and nearly stalling but then picking the revs up for a few minutes after dipping the clutch but after a 270 mile motorway drive it was all sorted, I just assumed the battery didnt have enough charge as they had been leaving the ignition on with the stereo on for ages.

SpaceCowboy, do you have another battery you could drop in it to see? Or take the battery out and undo the little caps on the top of the battery with a 2 pence piece and see if the levels are ok.
 
TheSpaceCowboy said:
Dubplate are you sure yours isnt the choke?

thats what i thought it was though my Mk3 Golf GTi has never started like this in the 8 years of owning it even on the coldest of days....
 
Maybe it is a problem then I always assumed mine was because of the choke, but I do get a fairly strong smell of petrol coming through on start up lol plus the fuel gauge takes a dramatic hit on starting in cold weather.
 
Dubplate said:
I missed this thread aswell.... my S3 on start up revs high for a few minutes and then settles, did anyone have an answer to this ? or the link to the thread ? :icon_thumright:

i saw this thread i think if i remember correctly is that if the battery is outputting a low value then it will increase the idle speed to increase the charge to the battery. when its at the correct value it drops off. i think this will also happen if the alternator is slightly faulty as the same output will happen/low voltage.
thats my understanding on it...i stand to b corrected.
 
TheSpaceCowboy said:
Maybe it is a problem then I always assumed mine was because of the choke, but I do get a fairly strong smell of petrol coming through on start up lol plus the fuel gauge takes a dramatic hit on starting in cold weather.

All those points EXACTLY the same as me especially the petrol. Hmmmm
 
Costco is a cash and carry type place they have a few up and down the UK but it is a big american chain. Only problem is you have to be or go with someone who is a member.
I think the bosch silver for my S3 was about 30-40 quid. They are pretty good for Michelin tyres also.

My S3 also revs high when first started in the cold. Never been worried about it. I like the smell of raw petrol in the garage ! It settles down after a few minutes.
 
Just another thought, if it was the alternator would the battery charge warning light not come up on the DIS???
I'm not sure myself might be worth looking in to though. My S3 has got 130000 miles on it and hasn't needed an alternator yet, I was pretty sure that the high revs on start-up was just the choke. Does it idle high if you start up on a warm engine?
 
No doesnt do it on a warm engine but then I thought, going by the other threads rationale, that could be cos the battery has been recently charged.
 
Looking at other posts, it is quite normal for revs to be high (up to 1200 rpm) on start up. Equivilant of the choke kicking and should only last a minute or so so I can discount that.

I think I will just get battery and Alternator checked rather than tryin to guess what the prob is. Cheers for all your help guys
 
I thought high idle speed on cold start is to help the cat warm up faster. Thats what I've heard before.
 

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