I replaced this part (Engine control module) and the transmission is not shifting hard as before, but the 'service engine light' and the 'traction off' light stays on.
Also the radiator fans will not turn on after the car has warmed up-and the temperture gauge doesn't move at all.Any ideas as to what is wrong?

My fans don't come on until gage reads 250, but as for the other things, you really would need a scan tool or have someone do a full diagnostic work-up. About $65 around here(non-dealer). Some members here have traced and fixed certain electrical problems, so maybe they'll have some ideas for you. Unless you're really strapped for cash, have it scanned. Not worth the time and stress.