The white paper that has the input/output list relates to the PLC. When you get the machine up and running take a small sharpie and mark each light that is on when everything is perfect and in working order. Then in the future if you have a shut down you can look and see which light is on or off that should not be and know where to look for the problem without having to go through the whole list. Ryko has listing for all the trouble codes like 04 that tells what it relates to. Have Ryko send you the list for your machine and keep it in a ZIP lock bag inside by your controls so you can easily reference them in the future. I am not a location right now to look up that code but later on I will try to swing by and look it up. The 2 digit trouble codes are generally pretty consistent throughout Rykos machines.
Double check to see if the small black breakers are tripped. They control the small solenoids for air etc. Usually located up towards the top left of the cabinet. I have seen them cause this code in the past. It is usually a bad coil on one of the solenoids. They run several through this same circuit breaker and the best way I have found to find which one is to reset it and watch the wash and see at which point during the wash the machine shuts down. The if for example it trips during trifoam wax unhook one of the leads to that solenoid and try it again to see if it trips. In my experience it is usually the small 24 volt dema solenoid coil that will need to be replaced. You can unhook one lead off the coil and run without it if it is not critical function. If it is critical swap it with a non critical coil and run until you get a new coil. I keep several on hand for backup.
If your machine has an FX2N or FX3U, please check PLC inputs X17, or anything between X70-X77. If any of those are still "on", you have a circuit protector or current relay tripped.