Need some help with this problem. I have a 1993 850, when i start the car the recerculation light and the aircondition light will start to blink for 30 t0 45 seconds and than the air light will stay on. When i go to slide the blower switch on from slow to high or auto, the blower will not come on. When i turn the air switch on and off i can hear the relay go on and off. Heat is coming from the vents. Thanks in advance, any input would be appreciated.

go to your on board diagnosis (in your engine bay besides your winshield filler neck) and check out the codes for your heating and ventilation system.

Chances are its either your blower fan or resistor.
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93 850GLT 430,000km * 94 850 300,000km * 86 240GL 360,000km

The 850 blower fan motor is notorious for freezing in cold weather. Do you park outside? Best thing I've found to do is to pull the HVAC codes and see what it says. It will probably say that the fan motor is pulling to much amperage, in which case it automatically shuts it down to protect the sys. If this is the case... I would pull the motor out and lubricate the shaft ends and bearing well with a silicon or teflon based lube... prefferably teflon... spray can should say asomething like PTFE or "dry lube". These types of lubes will keep the condesation from being able to freeze the parts together. Lastly... clear the codes from the hvac computer and reinstall the fan motor. Should absolve the issue. This is all assuming that the fan motor is in good working order and not actually just worn out and "seized" up. Good luck!

After reading the code 4-1-1 blower fan: over current or seized fan. I replaced the blower and the problem is still the same as it was with the old blower, but now i get the same code as before 4-1-1 and a new one 4-1-8 which i think refers to the power unit has no control signal. Where do i find the power unit? Any help would be appreciated. The car is always parked inside.