Sorry to say but what happens is the dealers don't want people trying to work on there own truck so what they sometimes do is change the factory pass code from all fives to something that they know it almost impossible to get the correct combination. If you somehow can fix it the light should go out by it self. You might have to call the dealer and have them bring over there lap top to tell you what code is in the dash or have them change it back to factory codes. the problem is it won't be cheap but then you might throw parts at it and not fix it. I will tell you that some of the injector on the 2.4 would go bad the only problem is there not available anymore you can get a rebuild kit to try to fix.but like l said only a guess.