This worked for me on my 2005 T& C. Remove the IOD fuse for a few minutes. Reinstall. Turn van on. Guages & lights will go crazy, but will reset.
I also saw on some older models, you could hold down the tripometer button to reset. One post said to hold it down and turn on vehicle to reset. Another said to turn vehicle on and hold down until it starts to reset. This didn't work on mine.