I have a 2000 S70 GLT with over 100,000 miles on it. (Currently at 137k). I had the transmission rebuild about two years ago at a Volvo dealer. (Close to 30k after rebuilt transmission and problem as been reoccuring in the hotter months on drives over 1.5 hours) Over the past few months the check engine light has been illuminating occasionally with a variety of transmission codes. <p>This happen before I rebuilt the transmission and tranny was in limp home mode. Now the transmission doesn't enter limp home mode and works perfectly. The error lights ONLY ever come on when the outdoor temperature is above 60 degrees F.<p>The engine and ttransmission have been running fine throughout this period. It is time for the vehicle's inspection and now the codes cannot be cleared. It seems to me that I may have a problem with the transmission computer module. I was thinking about sourcing a used computer to replace the existing unit. <p>Does anyone know whether a used computer will work in this application? I am concerned about the cost if I take it into a dealer...money is very tight for me right now. <p>Any estimates on the costs of replacing my transmission computer if I can't use a used one?