Here is the contact info for the company. It's a bit silly they don't have the the fault codes on their website. http://www.cat-lift.com/_cat/index.cfm/north-america/english/company/contact-us
It's early days, mate. Hopefully someone who knows the answer will see your question.
I found something. If the fault codes are universal to all Cat trucks then this might help. http://www.torrents.net/find/caterpillar+303+service+manual+free+download/