I have a similar problem that I have seen mentioned here (OD light turns on randomly and my gear shifts down to 3rd gear). So I read the discussions on this message board (excellent by the way!) and was looking for the OD relay. Upon doing so, I accidently found another relay that was also behind the glovebox but this one was clamped on the right side (way behind the right passenger AC vent). At first I thought this was the OD relay, but after more careful reading, I realized it was not. But just out of curiousity, what is this white relay for? It has six prongs that connect to its outlet. By the way, what happens if I just disconnect the the OD relay, will this cause the OD to constantly stay on and not give me this problem anymore? Because I have learned to hate overdrive and will gladly do without that option!
Also, what and where is this OD solenoid you guys mention?
If I wanted to re-solder my unit, what supplies do I need to buy at the autoparts store?

Sorry about the length of this but I love my brick and am trying my darndest to keep it alive before my drive back to Texas from Florida.

'92 Volvo Stationwagon 200K miles