2002 V70...The alternator cycles on and off at a frequency of about once per second. Light says to check charging system (thanks) and the batterylight is on.

I'm hoping there's an alternator relay separate from the alternator? If so, where???

Many thanks
Rob

 

Sounds like a bad Voltage Regulator.

 

I believe you're right. It stoppped cycling and stopped charging altogether. My voltage is dropping past 11 volts. I'll put a battery charger on it and get to the dealer.

I'm just happy that it is available separately from the alternator.

Thanks for the support.

Rob

 

No problem anytime.

 

Can you change the regulator without removing the alternator?

 

Some have done it but it is a MAJOR pain to do it.

 

I'm gonna try. Looks tight by the exhaust manifold, but otherwise OK.

Garage 1 says not till next week, garage 2 says we'll only change the whole alternator. So out come the wrenches.

What's the easist way to differentiate the 120, 130, 140 amp alternators so I buy the right regulator?

 

It will usually say in the regulator itself which one it has. But it will say something like 70-120 amp. You have a 120 Amp.
Or if it says 90-140 you have a 140 Amp.

 

Success!!

The aft cover screw was impossible to get at. But I was able to pull the cover back far enough to allow access to the regulator. Three phillips screws later I had the old one off.

New one went on with no problem.

And it works!!!

Yahooooo!

 

Glad it all went good!!