Alternator overcharging?

[WillieG]

Hi Folks,
2017 Berlingo owned for 4 months - battery just died, notice from service history was replaced new 11 months ago. (Yuasa)
After fitting replacement, checked charging voltage, and appears to be continually 14.95V to 15V, measured with with good voltmeter.
Seems too high to me, and thinking this may have caused the early demise of the previous battery?
Am I looking at replacement alternator or regulator, or is there anything else that could be causing this seemingly high voltage?
Finally, it is fitted with a stop/start battery, although my vehicle does not have stop/start - could this be a problem?
Many thanks in advance.....
Willie

[Sol]

It's likely to be the alternator / voltage regulator on the alternator. That is too high, should be 14.4v max roughly.

[Pedronicus]

11 months old battery? Still under warranty?

[WillieG]

It's likely to be the alternator / voltage regulator on the alternator. That is too high, should be 14.4v max roughly.

Thanks for the reply, Zion - yes, that's what I was suspecting, was just wondering if the ECU had any influence on the charging settings?
Oh well, time to source a replacement alternator then
Cheers,
Willie

[WillieG]

11 months old battery?  Still under warranty?

Possibly, but not if it's been cooked by an over-enthusiastic charging regime, I would assume?

[Sol]

The ECU doesn't control the charge voltage but there is a smart battery monitor built into the positive terminal. Maybe worth checking the connections are all clean and right.

[WillieG]

The ECU doesn't control the charge voltage but there is a smart battery monitor built into the positive terminal. Maybe worth checking the connections are all clean and right.

Good info, thanks - will check that in the morning before I start looking for an alternator.

[Sol]

And measure the voltage between the inner wing earth cable bolt on the passenger side, and the centre of the Lead battery + post, to be sure the voltage is actually reaching the battery. If it's 15v at the Lead post, then I'd say the alternator is the problem - some garages will have a DC ammeter tester to see what current is being sent to the battery too. High voltages can buckle the plates inside. Not sure if a stop start battery needs a different alternator in the cars which have it, as the battery chemistry may be different.

If it's a lot less at the Lead post, then the connector voltage may be high because the load of the battery is not actually being "seen" by the alternator (bad connection etc)

[WillieG]

And measure the voltage between the inner wing earth cable bolt on the passenger side, and the centre of the Lead battery + post, to be sure the voltage is actually reaching the battery. If it's 15v at the Lead post, then I'd say the alternator is the problem - some garages will have a DC ammeter tester to see what current is being sent to the battery too. High voltages can buckle the plates inside. Not sure if a stop start battery needs a different alternator in the cars which have it, as the battery chemistry may be different.

If it's a lot less at the Lead post, then the connector voltage may be high because the load of the battery is not actually being "seen" by the alternator (bad connection etc)

Thanks for that - all checked out OK.
Ordered a new voltage regulator, going to try that first - complete alternator is £230
Thanks for all the replies