Battery Light on mid-corner

[A.moser26]

Hi all, I just wanted to see if any of you knew a issue I've been having recently. Mid-corner the battery light on my dash flashes. It also comes on if I do a pull in a straight line. I'm not sure if its the alternator or regulator cause when I get above 4k rpm I've seen the voltage get as high as 16.5-17v. Thank you!

[maw1124]

Have you checked the terminals?

If so, you might need to check grounding points.

maw

EDIT... sorry, incomplete thought... if not those then yes I would suspect charging system, maybe a pulley on its way out.

[Shonky]

Pulley is not going to cause the voltage go high. Voltage regulator or just replace the whole alternator.

[A.moser26]

I checked battery terminals and the battery itself and its all good. I'm going to order a new alternator and voltage regulator and swap them out. I hope that fixes it

[SteelGreyM]

A new alternator comes with a new voltage reg

[A.moser26]

Thank you! I would have ordered both by accident then. How do I know which alternator to order? I see theres a bosch and a Valeo one

[Flow]

Valeo is OE
Watch out for reman'd units that might not be the best quality.
The light only coming on mid corner is very strange though, as overvoltage might happen at higher RPMs but isn’t linked to lateral forces. Maybe sustained higher RPMs without shifting during cornering is what triggers the issue.

[SQ13]

Had this issue at the track in the corners a few years ago. It was the alternator.

[sapote]

I checked battery terminals and the battery itself and its all good. I'm going to order a new alternator and voltage regulator and swap them out. I hope that fixes it

I don't think alternator glitchy when under acceleration (straight or cornering) unless the brushes are worn too short. I think you should check the tightness of the big red cable at the alternator rear nut and at the starter 13mm nut.

[Shonky]

I don't think alternator glitchy when under acceleration (straight or cornering) unless the brushes are worn too short. I think you should check the tightness of the big red cable at the alternator rear nut and at the starter 13mm nut.

But that wouldn't explain the high voltage occasionally.

[sapote]

But that wouldn't explain the high voltage occasionally.

Intermittent bad electrical connection on the charging cable can cause Load-Dump which causes high voltage.

[A.moser26]

I ended up ordering a new Valeo Alternator. I went for a quick drive yesterday to test, and it started doing it in a straight line now. Definitely either the alternator or the voltage regulator going out. Gonna park it till I get the new alternator in. Already blew both high beams out.

[Obioban]

The battery light only ever means the alternator/voltage regulator. So, that.

[sapote]

I ended up ordering a new Valeo Alternator. I went for a quick drive yesterday to test, and it started doing it in a straight line now. Definitely either the alternator or the voltage regulator going out. Gonna park it till I get the new alternator in. Already blew both high beams out.

Just make sure you replace the correct part: set the dash display to the hidden menu to show batt voltage, not driving but slowly rev rpm up while watching the displayed voltage and if it's going higher than 14.5v then this proves the regulator is bad, as there is no acceleration to cause the intermittent connection movement.

Don't break you back doing remove/install the alternator: Use a large socket as spacer to pull the slide-nut at the lower rear of the alt -- just 1 turn -- to free it from the oil filter housing bracket. You can use the same bolt removed from the front.

[bigjae46]

A new alternator comes with a new voltage reg

It actually does not in many cases.

If it isn't a daily, I recommend replacing the regulator and see if it goes away.