i have a 2002 ds and i just changed my oil and never bleed it, just cranked it over till the red light went off, worked great, i thought only the 2000 ds650's needed to be bleed

 

Your oil prssure is only 7bs at idle and 40 something at about 6k. I don't know how you could test the one in there now. But yo could always ge a mechanical one and use it instead. Then you'll always know for sure. As far as when you have oil at the filter. Yes I would say your oil pump is doing it's job. How well is it doing..Dunno

 

I have an '01, I've changed the oil about 20 times and have never had to "bleed" the system, the bleeder screw has never been cracked. but its there for a reason and one of these days I may need to if things just fall the right way.
but if you got oil in there then it seems its plenty primed, and the oil pump is such a simple device it is doubtful it has a problem. even if the relief valve was faulty and you had low pressure the light should go out because its cracking pressure is very small, like 5psi or something.
the pressure switch is $8 at the dealer and I always carry a spare everywhere I go because they die, I've replaced mine twice - once because I'd never get a red light, once because it wouldn't go out.
If you're really worried, get a 1.5" pressure gauge 1/8"npt and screw it in place of the sensor and see what it says. this is the end-all of suspicions.

 

I had my 2nd oil pressure sender go out when I changed oil last week. Pull out the sending unit and crank over the motor. If oil is pumping out the hole, at least you know the pump is ok. The sending unit is relatively cheap as stated earlier. My 01 doesn't need the bleeder cracked open after an oil change.

 

makes me wonder why no-one believes the 2001 bombardier service manual when it says to bleed oil????

you can have either low oil pressure or high oil pressure from not bleeding. you taking a chance on damage by not bleeding. in other words, not every change will require it but some will. gamble on.

the red light is a very low pressure dummy light and doesn't tell you that you are within normal operating range.

 

Well I'm pretty sure it is my oil pressure sensor. I unplugged it last night and the light goes out. There is a green retaining ring inside that is falling apart and it looks like it may have gotten some water inside of it. I did wash the DS a couple of days before doing the oil change so it probably went out then. I removed the sensor, cranked the engine and have oil coming out. I'm pretty sure I have proper oil pressure/flow. I'm going to head to the dealer this week and pick up a couple of new sensors.