It started off as the usual, alternator workshop light came on.
My question is has anyone measured the voltage on the blue exciter wire with ignition off? Unlikely because why would you ..
Replaced alternator with a super cheap gamble eBay one that had been refurbed and in use since fitted over the last few years, indeed brushes were good but this one didn't work either
So I go for new refurb unit, yes I know they can be iffy but it was reduced to clear, has "warranty" we'll see
Fitted and connected, I notice this faint hum when the ignition is off, real faint but definitely from the alternator, goes when the exciter wire is unplugged. Checked the voltage on the exciter wire, 2.8v no keys in the car, no lights on dash etc.
Interestingly I've suffered from battery drain for a few years now
I assumed it was related to the intermittent boot light as a result of either the infamous boot latch micro switch which was extensively tested and ok or the CCM which took a bath years ago. I never got round to getting at the CCM again to recheck for crusty connectors. I opted for the lazy approach and fitted an oversized battery and left a solar panel in the boot which fitted in well with what the car gets used for most often.However I've never heard this alternator hum before, I would have done surely at some point when my head's been under the bonnet. I thought I'd change the regulator assembly with the genuine valeo one that came on the previous alternator in case it should "ignore" this 2.8volts.
Fitted and reconnected and bingo, no humming, but I thought I'd make double certain and used the screwdriver to the ear method. I can now hear a rapid ticking/clicking noise, again only when the exciter is applied, ignition off still. Can only be heard this way so would have gone unnoticed.
I'm fairly certain there should be nothing on the exciter when the ignition is off, I'm just after some confirmation that a meager 2.8v is unusual before I start looking for a fault that's not there and I still have a dicky alternator which I think is ok, 14.4v on idle, no warning light and no AC at the terminals when the engine is running.
Thanks in advance
