I have a 2010 xc90 power system service urgent alarm. The battery was tested good at 12v. In order to start the car however I do need a jump and car seems to idle fine while still connected. Within minutes of disconnecting I step on gas and nothing happens and the alarm comes back. It is also visible how all lights go dim struggling to stay on. The engine seems to have a rattling sound coming from alternator area.

Now my car is stuck dead in the garage and cant get to a shop without getting a tow. Can anyone confirm if they had this issue and is there a trick to keep engine running so I can get to shop 1 mile away? I was also thinking it would be great if a mechanic can work on this in my garage in Bergen County NJ area.

Thanks

 

It sounds like your alternator is not charging. If you have the 6 cyl engine a common problem is the one way clutch on the alternator seizes and pulls the alternator drive gear loose - causing the alternator to not spin. Without an alternator you might be able to drive the car a few miles with a fully charged battery using as few electrical items as possible.

It is common for this to be diagnosed as a bad alternator - when in fact the alternator is ok, it's just not spinning because the drive gear is loose. If it's not spinning for that reason, a new one way clutch (the alternator pulley), possibly a new drive gear (if the mating surface is damaged) and some new orings for the intake manifold that is removed are the only parts needed. (other than possibly a new battery if it was discharged badly)

A special tool is needed to replace that alternator pulley - so you might want to choose your service provider based on their experience with Volvos and if they own that tool - otherwise they will try to sell you an alternator that might have the pulley already attached. The alternators I would get from Volvo did not have the pulley attached.

 

Hi thanks for the great information regarding the alternator clutch. I just checked and the alternator shaft is spinning so probably points to the alternator as the problem. I was leaning towards getting the alternator replaced and hoe for the best.