My car (Fiat Grande Punto MY2008) has been having an occassional battery light and failure of the power steering. Perhaps once in every 10-15 startups, and is resolved by restarting the car.
The car starts fine, but I am concerned the alternator isn't putting out enough power. So I have taken some readings, which seem a little on the low side to me but not bad enough to strongly indicate the alternator is faulty.
I've taken battery voltage readings, which are as follows:
- with engine off: 12.4v
- with engine on (idling)
- no electricals on: 14.1v
- some electricals on (fan at max speed/aircon/lights): 13.8v
- whilst turned steering wheel with above electricals on: fluctuates, but stays above 13v
- all electricals on (above + rear windscreen heater): fluctuates, drops below 13v
I ceased testing with the rear windscreen heater turned on, as the voltage on the multimeter kept dropping and I was concerned it would drop below 12.4v
Applying some revs to the engine didn't make a noticable difference to the voltage. My understading is that the alternator should output almost 100% power at idle speed anyway. The battery is new.