what do I need to do when the "service engine soon" light illuminates

clearing a code fixes nothing. there is a problem and it needs to be checked by a shop and let them tell you the failure and get a bid. Roy

The fault codes stand for car troubles. You need to get the fault codes and know what they mean. Then you will have the aim of where the trouble is and how to fix it. If you want to fix the problem yourself, these two tools may helpful. Nissan consult 4 is stable but a little expensive (http://www.chinasinoy.com/wholesale/nissan-consult-4-for-nissan-infiniti-and-newest-renault-1165.html), and NISSAN N607 (http://www.chinasinoy.com/wholesale/nissan-infiniti-professional-tool-n607.html).