Is my alternator about to die?

toyotacelicagt4 · 20 Sep 2014 at 15:26

Afternoon all,

I'm after a bit of advice on my 2004 zafira gsi in regards to the alternator. From the last few days I've been hearing a faint whining noise which seems to be coming from the alternator area. I've used a multimeter and have had the following results. Does it seem that it's on its way out?

12.4v on battery without the engine started
13.9v with engine started but no lights, radio etc on
13.25v with engine on and lights, heater, radio on

Thanks in advance

andythelandy · 20 Sep 2014 at 15:31

Those voltages look perfectly normal, that era of Zafari/Astra have electronic power steering pumps which whine all the time it's probably this you can hear.

Orionaut · 20 Sep 2014 at 17:53

A whining noise from that part of the engine bay is more likely to be belt/pulley related. So either an alternator bearing or a bearing on any of the other pulleys may be the cause.

it is worth investigating properly since you dont want it to be one of the guide pulleys for the Camshaft/Timing belt!

toyotacelicagt4 · 20 Sep 2014 at 18:44

Orionaut said:
A whining noise from that part of the engine bay is more likely to be belt/pulley related. So either an alternator bearing or a bearing on any of the other pulleys may be the cause.

it is worth investigating properly since you dont want it to be one of the guide pulleys for the Camshaft/Timing belt!

Might look at the bearing on alternator as I replaced the timing belt kit and water pump around 1k miles ago