Codes Pulled.....What do they mean?

OK, the following codes were pulled from my van today. My van is sputtering pretty bad now.

The first one is self explanitory:

P0300 - Random cylinder misfire

The second and third I have no idea what they mean:

U1000 - Class 2 serial cam problem

P1626 - System fuel enable circuit

Anyone know what may cause these?

thanks for you help

I have a list of codes here (http://www.my-chevy-venture.com/dtc-list.html).

They are from the GM manual and have a little better explanation than what you have above.