air bag code42

any help on airbag code 42? on a 03 expidition when you first start it the airbag flashes 4 times pause then 2 times then just stays on any ideas would be helpful thanks !!!

The problem you have is a fault in the front impact sensor. That's what a code 42 means.
Here's a site that will explain everything you need to know about airbag lights and resetting the system.
http://www.airbagsolutions.com/

This website gives you the procedure for diagnosing and resetting airbag lights. See if your car is listed here. Although it’s a pay site ($14.95/day), it’s a lot cheaper than going to the dealer
http://www.airbagsolutions.com/vehicles_list.aspx

On most vehicles, the airbag light should come on for @6 seconds, and then go off if the system is working properly. If there is a fault or a problem in the system, the light will remain illuminated, or flash continuously. If the airbag light does not work properly, some vehicles have an audible tone that sounds indicating a problem with the airbag light system. When the light is on (or the tone is sounding), the airbag will NOT deploy, even in an accident.
The flashing light on your car is telling the answer you need. On some vehicles, the light is flashing a two digit code. Once you know the code, you can most likely repair it yourself. There are fairly easy procedures that most people are capable of repairing.
Airbagsolutions.com has the fault code charts to tell you what is wrong and how to fix it!

Some vehicle manufacturers accommodate systems without a scanner (like Toyota, Lexus, Nissan, Infinity, Honda, Acura, Ford, Lincoln, Mazda & Mercury) and some require a scan tool.

Check out these websites also for more info on airbag systems and the light.
http://blog.airbagsolutions.com/archive/2007/11/18/why-is-my-airbag-light-on.what-should-i-do.aspx

Lastly, check your vehicle for recalls through this link also:
http://www.airbagsolutions.com/nhtsa.aspx