In my '93 850, my transmission mode selector switch (sport / winter / economy) was broken for a long while (there was no lights on it at all). I got a working switch from a junkyard and plugged it in, and now the lights on it blink. The sport light will blink if sport mode is selected, and the economy light will blink if economy mode is selected. The up-arrow light on the dash also blinks. I did a search but didn't see anything about blinking mode selector lights. Any ideas? Thanks.

 

You have fault codes in the trans. Scan.

 

Could be a few things. The relay's have been known to go bad. Could be your PNP switch. Turning your Key to the II position then "row" the gear selector rapidly from Park to 1st (up, down, up, down) with out pausing 15 pr so times. This can temperately fix the issue for you. I have the same thing going on in my 97 850, but it's from third gear inside the trans shifting over and clipping the Vehicle speed sensor.
Also when you do a search, search for "transmission up shift light"

 

Yeah, I was more curious about the blinking mode lights, I haven't seen anyone post about those before. PNP is getting changed this week, hopefully that's the root of my problems.

 

So I replaced the PNP switch and cleared all the codes. No more blinking mode selector or arrow on the dash. Hope it lasts!