I am new to working on these units. I have retrieved the codes out of the machine by reading the flashes. It seems to be 3 5 3 followed by 1 2. I am guessing that 1 2 is end of code list, but I am tring to find out what 3 5 3 means. I would also love to have a complete code list if someone has one as well as a service manual. The problem with the machine is it backfires on startup and has a loss of power.
I have read that you can hook up a laptop to these units. Does it require a special interface?

Thanks for your time