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Flat battery

polar964

polar964

PCGB Member
Member
Hi folks,
Took car out last night, after about an hour an half, just before dusk had lights on, the ABS warning light came on together with warning sound. Pulled over in layby to check whether it was a spurious fault ! Turned ignition off and guess what, car wouldn't start, not enough life in the battery. Sat pondering for 5-10 minutes then tried again ... it started, thank goodness, taking no chances went straight home, however as soon as i switch the lights on, the ABS warning light came on together with audiable sound.
A new battery had been fitted in March 2006, but checked it anyway. Put a volt meter across it and it read 12v droping to 11v, checked each cell with a hydrometer, each cell registered totally flat. Although i turned the ingnition the car did start. Allowing the engine to idle this showed no increase in voltage even when reved slightly.
I am lead to believe that an under voltage condition is indicated by the illumination of the ABSwarning light although the warning sound should not be heard??
The alternator was replaced in November 2002 and has only covered approx 14000 miles since then.
Do any of you guys have any answers or suggestions. Hope you do !! Cheers

Paul

 
If battery was replaced last March it should still be OK now. Alternator should also last longer than 14000 miles. If the alternator brushes alone were replaced and the slip rings were grooved from the previous brushes then another repair maybe required. Anyway charge battery/ check charging rate with voltmeter approx 13.5 volts with engine running. If 13v is not reached then ABS light will not go out. A silly question but I take it you have checked the alternator belt !! Cheers.
 
Yep checked belts ok. Battery is currently on charge. When fully charged will check voltage again. Thanks for replying
Paul
 
Most likely you have a current drain somewhere. A new battery will last at least 2+ years and if the alternator etc are all working, then something is flattening the battery. Easiest way to check is to charge fully the battery, put in the car and if 2 days later it is flat(ish) then you have a light on, short-circuit, etc somewhere. A good battery should be good for 3 weeks minimum before the residual drain/alarm etc takes it down. If it stays good then the problem is in the charging of the battery, not the draining of the battery. Good luck!
 
Thanks for the tips guys.
I have since heard that the charging system on the 964 is pretty poor any way and once the battery has had the stuffing knocked out of it the system is not particularly brilliant at maintaining it, even after a recharge. Will be interesting to see if the voltage changes once the battery is charged and the engine is running.
Will let you know how i get on.

Cheers Paul
 
Is it just me or do others want to rush out and buy a new battery when you read threads like this because you don't know when your's was last replaced?[:(]

I think I'll do it! What's the spec again? 75 Ah? And is it the Bosch Silver that folks recommend?
 
The Bosch Silver 7HN (75AH) is ideal. If you have an account (or access to one), Costco sell them at a better price than anyone else I've found. I paid £55 (inc VAT) for mine last May although prices may have gone up some since then.

Regards

Dave
 
ORIGINAL: Computamedic

The Bosch Silver 7HN (75AH) is ideal. If you have an account (or access to one), Costco sell them at a better price than anyone else I've found. I paid £55 (inc VAT) for mine last May although prices may have gone up some since then.

Regards

Dave
Click to expand...

Thanks for the good advice as usual Dave. I've just picked one up from my local Bosch supplier (an automotive trade counter). Having the exact battery type details really helped. It was £75 including VAT. I was quite shocked at how big it is (my current one is a 55 Ah battery). It looks like it's going to be a snug fit!
 
Quick update folks
Finally relented after much discussion, advice and checks. The alternator is now out of the car. Hope it goes back as straight forward. The hardest part, beleive it or not was the three allen bolts which hold the second pulley. They only have very shallow heads for the allen key socket so care must be taken to ensure the wrench is fully supported when force is applied. I sure thought i was going to screw the heads right off. Will replace these with new ones just incase they have to come out at some later date. Good oppotunity to refub the alternator housing and cooling fan while the alternator gets a thorough check and possible overhaul. The bearings don't seem as smooth as i would have expected seeing that it was supposed to have been a new unit 14000 miles ago.
Anyway hope i am a little closer to resolving this little problem.

Paul
 
Just for info really. Just replaced my battery & was £57 + VAT from Costco Reading. Bit like a kiddie in a sweetie shop though, bought oil, cleaning clothes etc.

Jonathan.
 
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