Chrysler Repair: 04 Concorde: Check engine light, 4 digit numbers, chrysler dealership

Question
I took my car into have the recall work done on it and since then, the engine light has been steady coming on and the first time i thought it was due to the cruise control, but after calling in the chrysler dealership that done the recall work they said after about 3 good drives it should go off, which it did, but in about 2 weeks, it's back on again.  Any suggestions?  Thanks!

Answer
Hi Leeann,
Try using the ignition key:"on-off-on-off-on and leave on" doing that switching in 5 seconds or less elapsed time. Then watch the odometer window of the instrument cluster to see if the mileage changes to show 4-digit numbers prefixed by a P. If so, those would be fault code numbers that are stored in the engine computer whenever the check engine light comes on. If that doean't produce any results then go to an Autozone parts store where they will likely get you the codes via reader that plugs into a socket under the dash by the steering wheel. Ask for the code number specifically then let me know what they are. You can ask them what they recommend doing but feel free to let me know first before you pay/but anything. If there is no such parts store nearby then an independent shop will probably do the readout for under $40. Also tell me which size engine is in the car.
Roland