Flat battery

[Alistair C]

Driving along this evening and the Autocheck flashed up Battery voltage too low (the battery symbol).
A few minutes later and the ABS light came on and the PAS I believe lost its speed sensitivity.

The alternator 'low charge' light never came on though.
Battery voltage is now at about 10v but won't come clost to starting the car.

The battery was new exactly two years ago.

Any suggestions or thoughts (including how I can get to work tomorrow!) appreciated,

[quattronutter]

either your alternator is shot,battery is crackered or you have something draining the battery,best to check alternator output first,you should see approx 13.5 volts,if not it has seen better days,try tapping the alternator,sometimes the brushes stick,you can test output with a multimeter....

[Alistair C]

well, where I can get a good connection, the alternator is putting out 13.56 volts.
(even though it is just a pony 90A version. Sure it should be a 115A if it has AC.... nevermind )

The voltmeter in the car just will NOT show anything above 12.2v

Time for a new battery? or is there anything else to check??
Cheers,

[quattronutter]

get your battery tested with a hydrometer,that will tell you if it has any dead cells,thats assuming its not a sealed for life battery..

[Alistair C]

Will do - just reluctant to go out now knowing it could grind to a halt anywhere.....

I'm starting to dislike this car....

[Jamo]

Sounds like an earthing issue to me

[Alistair C]

hmm - just read a thread by Tom describing similar issues on a customers car.
(http://www.s2forum.com/forum/showthr...hlight=battery)

Turned out to be a completely broken engine earth strap. Anyone know where this is attached? Bit hard to see in the dark!

[SR71]

In my experience, they just fail.

Happened to me twice now. Once with my GT4 and about 5 months ago on the S2.

Start fine. Then one day, they just pack up. Luckily, the time it did it to me in the S2 I was at the Audi garage! But the time before that, you'd never have guessed that the next time you went to start the car it was going to pack up.

[Alistair C]

In my experience, they just fail.

Sorry mate - what are you refering to? Battery / Alternator / Regulator / Earthing ?

[jameswkr]

Engine earth strap. 2 on the middle of the inlet manifold on my S2. I have read of others too. Anybody ?

[WabTheKing]

i forgot to put that earth strap back on when i had my engine out, it basicly cooks the voltage regulator

ive had the exact same problem!!!!!!

[SR71]

Sorry mate.

I meant the battery.

Nothing whatsoever to suppose the battery was going dead. No lights etc etc. Stick a new one on and off she goes again.

Even the voltage looked right. However, on cranking...well it wouldn't.

I wouldn't have believed it possible if you'd told me.

[Alistair C]

This is probalbly optimistic - but don't suppose anyone has an image they could share which'd show where the straps should be? I know my engine's been out so it could be missing & I'd be looking forever!

[Alistair C]

To give closure to this topic, it was a duff alternator.

We tried a new voltage regulator first. This gave no charging at all and left me stuck on the M25 after having it changed by Dialynx.

AA put the old VR back on and this seemed to work once the engine had revved over 3000rpm. (AA managed to break the new VR getting it off roadside.)

About a week later the car stopped charging altogether.

Bought a replacement alternator, bolted it up & problem fixed immediately. Genuine Bosch reman from Camberly Auto Factors cost approx £90?

(Oh - and as a side note, whilst the car was with Dialynx, they also changed a steering tie rod as the BJ was damaged. They neglected to even consider alignment & by the time the questionable 'wandering' steering was diagnosed (at great expense by Quattrosports), Dialynx's work had cost me 2 front tyres. Not a good experience.)