I've checked the error P0843 and it relates to the 2nd clutch switch. However going on line the commentary is change the switch and if that doesn't work change the fluid. The cheapest switch I can find on Amazon is ~$40. To do a complete change of fluid (3 refills) will cost $95 just for the fluid. Is there enough experience out there to determine which is the more common problem, the switch or the fluid? There's 100,000 miles on the car and I've had the fluid changed once. The other observation is the transmission still shifts smoothly. Thanks for any help you can give with this problem.