Alternator voltage regulator replacable?

[KennyP]

My alternator stopped charging. Turned my car on today and few moments later got a "battery not being charged" message on idrive screen. So i pulled out my Cobb Accessport to read codes and check battery voltage while engine is on.

Accessport showed P2E97 code and when i cleared it it quickly came back.
P2E97 is alternator related code as far as i have been able to find out.
Also checked battery voltage via digital gauges... It showed only 10 volts while engine was on and revving did not change a thing. Im guessing it should be around 14 volts while engine is running and charging the battery.

I havent heard or read anything on alternator replacement on Z4 forums.
im guessing it not that common for them to fail?

I have seen threads and videos on e90 335i where they replace Voltage regulator on the alternator as its a separate part. Newtis even had a repair guide on that for 335i.

But Z4 doesnt have the same alternator. 335i has 180A and Z4 170A alternator. And on Z4 35i alternator it seems voltage regulator cant be replaced. At least i cant find proper partnumber for it and also newtis doesnt have a repair manual for Z4 35i voltage regulator replacement.

Only thing i have found is a single odd ebay listing for a Z4 35i voltage regulator.
https://www.ebay.de/itm/284523956775...3ABFBM7oPHvc5g


Anyone here have had any issues with their alternator?
Has anyone replaced it? Aftermarket options?

New Bmw original alternator costs about 900 eur. There are two partnumbers for it: older one and a newer one... Older one is a bit cheaper on german webshop but it may not actually be available anymore.
Link to shop, includes partnumbers etc:
https://www.hubauer-shop.de/en/carpa...21198-generat/

There are aftermarket options from various brands around 300 eur. Has anyone tried and installed them?

Opinions?

[B21]

My friends 2013 20i alternator failed late last year..he sourced one for about £500..

Autodoc in Europe I’ve found to be very cost effective..

[KennyP]

Yes I have used Autodoc many times... Those 300 eur alternators i mentioned were on their website.
Can you find out which brand did your friend buy?


Also did some digging and found a full Alternator refurb kit for Z4 35i.

https://www.maniacelectricmotors.com...042106030.html

That made me think about sending my alternator to an alternator repair/refurb shop to get refurbished... Basically they would change out all the same parts as on this kit i found... Dont know if its worth it and how reliable would that option be...

[B21]

Originally Posted by KennyP

Yes I have used Autodoc many times... Those 300 eur alternators i mentioned were on their website.
Can you find out which brand did your friend buy?


Also did some digging and found a full Alternator refurb kit for Z4 35i.

https://www.maniacelectricmotors.com...042106030.html

That made me think about sending my alternator to an alternator repair/refurb shop to get refurbished... Basically they would change out all the same parts as on this kit i found... Dont know if its worth it and how reliable would that option be...

Decent shop should do a great job..obviously finding a decent one is the issue..

His was a N20 with different alternator…I see availability is limited on Autodoc at the moment…

It’s a low tech device so would go for the €300 versions or a rebuild..