2001 Volvo S60 na

[Alexis2929]

So the car first started reading low voltage and we decided that it would be the alternator because when we would check the voltage when the car Was on it would only read around 11 volts and I believe it’s supposed to be around 14 right?
So we got another one and this one reads around a 12.
So now I don’t know if I’m getting unlucky and the alternator just didn’t work or if there’s something else wrong with the car.
I’m honestly clue less and I hope it’s something simple like grounds or fuses because I don’t feel like swapping the alternator out again lol. But if I need to I will, at least I have experience now

[jonesg]

You read the voltage at the battery?
should be 14+v , might want to try reading it at the alternator big cable output.
Access is very limited, might be easier from below with car on ramps .

[oragex]

There's two readings

With the engine idling, you should see between 13.5v-14.5v (take or leave). This is your alternator voltage

With the engine off, disconnect the Neg (red) cable at the battery, let sit 30 min, then measure between the battery posts - you should get at least 12.3v, better between 12.5v-12.8v This is your battery health assuming the alternator is charging properly

The alternator may show around 14.5v for the few minutes of driving which is to top up the battery, then drops to 13.5v as the battery has been fully topped up

[Alexis2929]

You read the voltage at the battery?
should be 14+v , might want to try reading it at the alternator big cable output.
Access is very limited, might be easier from below with car on ramps .

I checked it at the alternator and it read around 12.3.
So I’m guessing it means I got a bad alternator ?

[abscate]

Yes, and a discharged battery

[oragex]

At 12.3v it means there is no voltage from the alternator, so you are actually reading - and driving on the battery alone. So the alternator doesn't work at all OR ALSO POSSIBLE the cables from the alternator are damaged. Also look around the engine at the grounds, like the rear one www.youtube.com/watch?v=tHLZpq7lNRk On the alternator there is two parts that fail: the alternator pulley, or the alternator regulator - the black piece with contacts. If the pulley is still good, you can just replace the regulator. Be sure to get a Bosch part https://www.fcpeuro.com/products/volvo- ... 51#fitment

[jonesg]

if the small signal wire from the ECM is corroded you will not get charge current from the alt.
It will not illuminate the RED battery warning, just low batt voltage in the DIM.
On mine the signal wire was full of green gremlins from the long winter without being driven 6 months.
I crimped on a new plug and alternator started working again.
See the pic, if it looks like that...

download/file.php?id=54732&mode=view

[oragex]

While there, there's a similar connector to the starter, also exposed and fragile - quite difficult to access

[Alexis2929]

Thanks everyone for all the reply’s i will be checking all the things you guys suggested and I’ll get back to you