hi,
you should replace the pnp switch at this age for in the winter the contact will float in the switch and cause a no start condition. but i think your tranny need a flush if you have not done one lately (colour should be red and not dark red or brown. flush it with 16litres of tranny fluid, it will made a change for the best.
(i have being working on these car for a long time. good luck.
email me at personaljb@hotmail.com

I had an intermittant problem that usually surfaced when the weather got cold. The tranny would upshift and down shift on its own. At highway speeds it would drop out of overdrive for no reason. Turns out I had a bad throttle position sensor. The tranny was not getting good info on how fast the engine was running, and could not figure out which gear to stay in. Replaced it for $125 or so, and all has been right with the (Volvo) world.

Bob Watson, 95 850

About the Check Engine Light (CEL): Codes can quite often be set without a CEL. Situations where timing is retarded, and the car drives very slowly, have no CEL, but there is a code set that needs to be reset.

I thought that was my problem on my 97 because I had the same problem on my 94.
Even shifted back and forth between gears and that cleared it up for a while.
But when I took it to the dealer they reset the codes and told me to come back when it happened again . Found out 2 of the 3 solenoids in the tranny are the cause. I also had the blinking arrow ,stuck in 3rd.
$915 to replace all 3 .
I said reset the codes and I'll think about it.
Haven't had the problem for a month ,but I know it will come back.

Often you'll get a flashing orange arrow in your instrument cluster.

j