kplonk

Hi,

came back to the car today to find it would not start. Checked the battery voltage and its reading 9.9V with the engine running (After some jump leads) its reading about 12.5V. Does this sounds like a dead cell in the battery. the car is a 04 sti done about 24K. Or do you think it may be the alternator? any one know if the battery is under the warranty?

Thanks Kieran.

harvey

iTrader: (48)

Most likely to be the battery but it can be checked in two or three minutes. Take the car to whoever is responsible for the battery for confirmation.
You should be seeing 13.5 plus volts from the alternator at 2000 rpm.
You could prove to yourself it is the battery by charging it for 6-8 hours, disconnecting it over night, reconnecting it and seeing how the car starts.

kplonk

thanks,

are there any issues with the alarm after reconecting it?

K

dan83590

I had a very simalar problem. Turned out it was neither alternator or battery, it was a short circuit between the alternator and ignition..

This was what gave a low voltage reading from the alternator. If you can get the individual items tested before you buy new then do so. Otherwise it could prove very costly.

D

rob84

iTrader: (5)

try checking the charging with the sidelights turned on so there is a little ammount of current draw i dare bet it starts to charge the battery my car does this its a complete pain in the ***. It doesnt charge the battery if there is no draw its to do with the smart alternator fitted to it it only works when its needed something to do with fuel consumption or so i was told but my car charges ok with the lights on but not without

st3v3

Your alternator should be charging at 14.4ish volts with your lights on.

Leg@cy

iTrader: (2)

take the battery to a car electrical place...... they should be able to put a tester across the terminals....

It should not drop below 9v within the first 15 sec.... (So I was told.... )


Mine never nit 9v and was told the battery was fecked........ luckily mine was still under gurantee

Phil

scoobyboy

you have the smart alternator that only charges when the ecu will let it, as above put the side lights on and it should start to charge due to the load chances are it's the battery

kplonk

thanks, got the battery tested and they said, its a gonna, so got a new one. The car has to go in for a service tomorrow and i asked them to check it all out then. Will have to wait and see.

Thanks all kieran.