volvo s60 - low battery voltage warning - Ralphh

Volvo s60 2001

I had low battery voltage warning, measured at 10volts.

Charged battery.

Monitored battery voltage, started engine, voltage rose to 14V then while driving some 8 miles the voltage gradually dropped to 11.5v. Parked car.

Started again, voltage rose to 14V then gradually dropped again.

Battery is 1 year old and appears good.

Alternator appears to charge ok after starting but then appears to give up.

volvo s60 - low battery voltage warning - Collos25
You are confusing voltage and ampage a really shot battery will probably read 14.v for a short time when you have just charged it .It is either not fully charged or there is a heavy drain when you switch off,of cause the battery could be US it needs to be fully charged and then a discharge test done to find its real condition.
volvo s60 - low battery voltage warning - Peter.N.

If you were monitering the voltage while driving it shouldn't drop much below 14v all the while the engine is running, if it is you either have a faulty alternator regulator or the drive belt is slipping.