2004 jeep liberty limited 4x4 airbag light goes on when you start the car then goes off for a few seconds then comes back on . both dash light and grab handle lights do this

The most probable reason for the code is the battery being dead for a while, there is a capacitor in the airbag circuit to make sure the airbag can go off in a collision even if the battery disconnects itself in the process. There is a slim chance it might be something else but either way the shop should be able to tell you what the problem is, and get it fixed; sometimes, scanner reader could helpfull to know exactly what fault code is stored there. keep in mind that this isnt an OBD codes reader, this is more specific for Airbag Systems.

Also, isnt rare to know that the airbag warning light is indicating the airbag(s) may not be functionig. As it says in the manual, "Ignoring the AIRBAG warning light in your instrument panel could mean you won't have the airbags to protect you, (or your passangers), in a collision...have the airbag system checked right away". Always wear your seatbelt. On 2004 there is a light on the passanger grab bar that indicates the passanger airbag is off. This happens when a child is in the seat to protect the child from the sudden force of an airbag. It can also be fooled by a package or briefcase on the seat. This is normal. When an adult sits on the passanger side the light should go off. This information was an addition to the 2004 manual.

Check THIS ARTICLE for additional details.

Hope this helps.