I have many fault codes, 132, 434, 435 in A-2 and 213, 214, 314 in A-3. While checking the output voltage of the o2 sensor, I noticed that it was a steady 16.21 volts for both front and rear 02 sensors. I though that this was wierd, and then checked voltage at the batttery while running, I got the same value. The car is a 95 850 turbo, with what I believe is a standard 100 amp alternator.
The question is, has anyone changed just the voltage regulator on an 850. I would guess that it is internal, like on a 240, 740, etc. Can the voltage regulator be changed with the alternator on the car? My guess is that the alternator is responsible for all of my fault codes. Any guess's or advice welcome.
thanks, Liam

Before jumping to any conclusion about the charging system, have it double checked at the battery with a device called a Vatt-40 (or newer model) as with that, one can test amperage, actual charging voltage under a load, etc. Any decent repair shop anywhere has a device like that.
If you measure anything near battery voltage at an O2 sensor, you weren't measuring O2 sensor output (which is less than 1 volt), you're measuring O2 pre-heater output from the ECU to the O2 pre-heater circuit. I'm also not sure that your volt guage is realiable so that's why I'd advise a better method. Although your shouldn't have 16 volts anywhere, one tests a charging system at the battery.

As for the codes: 132 is for battery voltage (too high or too low) but that can appear if the voltage went low at one time too (like a weak battery).
435,436 combined is USUALLY a vacuum hose leak (NOT both O2 sensors being bad) and those ABS codes (all for rear wheel sensors) usually indicate a bad ABS ECU (especially on '98 X70s where that's now common).

The voltage regulator can be changed out. Mine cost me about $115 US. Find a good generator and alternator repair shop and they should be able to do it.