Top starts to go down then stops.

There are only Two things in the right rear the pump motor and the top ajar switch. This sounds like the motor is locked up or the top is jammed or going the wrong way. First disconnect the motor and if the noise stops it's the hydraulic unit trying to move the top watch the top to make sure it's going the right way, the top ajar switch could be bad. If you're confident in the hydraulic unit and motor the only thing left is a jammed top, a bad connection at the hydraulic unit, or the top ajar switch. I hope this helps. Take care.

Any codes?Did changed an air filter? Dirty throttle body.

Check out the fuse for the convertable top motors. See if something is binding against the convertible machine motors or mechanisms or the material itself. Pull it up slightly to free any obstructions and try again. If you can, check to see if the relays for the vtop motors are working and see if you are getting power to all devices including the switckh on the dashboard.

Check to see if the top motor is running when you press the top up switch. Car has to be in park with emergency brake engaged. If motor runs but top will not move or binds then one or both of the lift cylinders are bad. Usually there will be hydraulic fluid leaking from the cylinders if one or both will not hold pressure. Replace cylinders if bad. The top could probably be manually closed if the lift cylinder arms are detached from the top frame.
If motor does not run when the switch is pressed then check your fuses, the switch and the connector at the top motor to see if it is getting power.

Open the pump bypass valve for the top to manually open/close top. Bypass valve is located in trunk on left; remove round 2" cover and turn the exposed valve anti-clockwise.
Problem of motor not moving top is likely low on pump oil. Remove cover on left in trunk and refill slowly after removing the fill plug on top of pump. Use 10w30 oil.

channels that it runs in may be full of grime! binding it up & the motor isnt strong enough to cope with that!
Cheers Rob.

you could have hydralic malifunction or low fluid level.air in system or you have mechanical binding.

This happenrd to me the first few times after filling the tank. When the roof stops push the switch to up then back until movement stops then go back to down, eventually it will get rid of all the air in the system and the roof should start to work.

There are a number of known issues affecting the 9-3 convertible top. TSB 811-1989 describes a problem and fix for the cables to the lock for the top cover.
TSB 811-2101 refers to the jamming of the top cover due to a deformed hinge and provides the fix for this.
TSB 811-2160 deals with instances where the first bow hits the top cover while the top is opening, due to a deformed shear pin, and provides that repair procedure.
Where the soft top cannot be operated or it stops in mid-operation, the SID displays the message CHECK
SOFT TOP COVER, and the following diagnostic trouble codes are be generated: B2025, B2026, B2030, B2031, refer to TSB 811-2236.
Any of these four problems can result in the top cover failing to open and close properly, and can interrupt the smooth operation of the opening and closing of the top.
Finally, the top may somehow have otherwise become out of sync and this does indeed require a Tech 2 diagnostic scan and programming tool to correct. All Saab dealerships have this tool, and an increasing number of independent shops that do appreciable work on Saabs are so equipped now.

possible that a commutator brush has dis-lodged from its holder...try measuring resistance to motor.....should be low around 2-5 ohms but not zero and not infinity.....the latter a clue to brush problem...the motor, if brush dis-lodged can be repaired...a matter of dis-mounting it and inspecting brushes then pry on brush with strong needle point to re-mount it....