Alternator issue (probably)

[Baj]

Part of the reason I have not been around for a while is I don't drive the Lolvo much at the moment (mainly as I can't afford to).

Recently I have been having flat battery issues which I put down to the lack of use. After a jump start from a spare it would be happy again.

Yesterday where the car did not have enough juice to unlock the car and when I opened the door the alarm sounded like a duck being strangled in a large tiled bathroom.
I jumped it and drove to where I needed to be. On completion of the journey it didn't have the power to lock the doors again. That should have been a clue but I assumed the battery was a gonner.

Today I swapped over the battery for the spare I had been using. Everything was smiley.
I put a multimeter on it and at idle it said 13.7v and it went up a little on revs.
I drove off on a long journey and after about 30 miles the battery light came on the dash along with a message about 'charging maintenance' or something. After a spirited rev it went away. A few minutes later I got a warning message saying battery low.
I had to turn round and drive home for fear of being stuck in the wilds of North Yorks. Low batt light on all the way home.

We went out again in a different car and 6 hours later returned home. I tested the car and it starts ok. Voltage is a static 12.1v which means it clearly isn't charging.

So:
1) I reckon alternator; do you concur?
2) are these the same across the range or does a 2002 2.4T have a rare and expensive version?
3) Anyone breaking an S60 and/or has a spare alternator?

[v70torslanda]

1. Yes
2. Check the plastic cover for the power output/part #. 140amp?
3. Readview, Salvo, take your pick.

[mds]

Change the Voltage Regulator Mounted on the back of the alternator.
One of the diodes will have died/fried allowing charge when running but draining the battery when engine off if two go no charge at all.

They are not hard to change and a fraction of the cost of and alternator.

[Baj]

And where do I get one of these Voltage Regulators?

[Baj]

Forget that. The fraction of teh price seems to be 9/10.

How universal are the alternators ie will one from a 2004 V70 D5 fit?

[v70torslanda]

Part numbers and ID codes are on the regulator itself and the plastic cover on the back of the alternator.

Visual check, number comparison.

If it waddles and it's quacking - it's probably a duck.

[Baj]

This guy seems to suggest they are pretty universal.
I have a parts quote from breakeryard.com for £58 inc shipping and vat
Scrappy in question seems to have good feedback so that will save me an afternoon in the mud in the rain

[mds]

Make sure its the right alternator for your car they come in 3 types 120amp 140amp and 160amp outputs.

I think 140amp are the most common but check the numbers as advised by V70Torslanda.
Most good Auto Electricians will have or get a voltage regulator a new Bosch Alternator is about £250 iirc and a Voltage Regulator £35 (also Bosch)