Fabia Power Steering warning light

Recently when starting up the power steering warning light remained on, if I restarted then it would go out until last night when no matter what I did it remained on! I have cheked fluid level, battery voltage is 12.2 and 14.4 with engine running, auxiliary drive belt tension ok. Any ideas?

Found problem to be voltage related - charged battery with 4 stage charger and now light goes out and normal power steering has been restored.