If you have a Fujitsu mini split remote, the fault code can be found in the user manual that came with your unit. If you don't have access to the original manual, then you can search online for Fujitsu Fault Code List and find one that lists all of the codes associated with your model. The codes will vary depending on which type of remote control and/or system you are using. In most cases, when an error occurs it will display on your remote's LCD screen along with an accompanying code number. Once you find this code number, refer back to your list or manual to determine what specific issue is occurring within the system and how best to resolve it.