EMB-145 flight crew reported low fuel indication during climb. Diverted and returned to departure airport.

Narrative

Flight XXXX; ZZZ to ZZZ1; returned back to ZZZ due to master warning Fuel Low level 1 then Fuel low level 2 EICAS Message. The flight was empty since it was a ferry flight to ZZZ1. Upon climbing through 17000 feet we received an master warning alert message on the EICAS as well as the alarm and silenced the alarm though the cancel button and this was happening just after we were given a reroute since the PDC showed the ZZZZZ Departure and after takeoff were told from ATC to proceed to ZZZZZ which was not part of the route since the PDC showed a reroute of ZZZZZ1 and then XXX to ZZZZZ2. So we were distracted with that initially and programmed the films with the reroute. So again we were climbing but ATC stopped us at 17;000 ft and the fuel low level message comes on. I removed the TCAS box and had the fuel page up and noticed all the fuel tanks showed 0 and were red. We ran the QRH which stated to land at nearest airport. We decided it's best to go back to ZZZ. In About 2 minutes or so after this the tanks went back to green but either we were running the QRH and we notified ATC of the issue and requested to go back to ZZZ as precaution. ATC asked if we were [requesting priority handling]. By the time I got back to ATC the tanks went back to green and so we didn't [request priority handling] but if it happened again yes I would have. The reasoning behind that was due to the fact the message went away but as precaution requested to go back to ZZZ. We notified Dispatch about the issue and explained what had happened and they relayed the message to maintenance control. Got the inbound ATIS and set everything back up in the FMS and the radios for Runway XXL and ATC gave us vectors back to the field. We ran the decent check list and the approach check and landed in ZZZ on Runway XXL and parked the airplane at the gate. Also prior to the approach check and on the descent I noticed the fuel tanks about 300 off so we cross fed. Prior to landing it looked like the tanks were going a bit off again so I mentioned that to Maintenance as well when I spoke with them. I Called the dispatcher once we landed and the Duty Manager and the Chief Pilot and maintenance met the airplane and looked up the issue and saw the FCU (Fuel Control Unit) was not working and failed. No fuel leaks the Maintenance said but the FCU failed. Either or as precaution we brought the airplane back to ZZZ because if not; say we continued on towards ZZZ1 and it happened again then what; and then there probably would be more issues. So rather be safe it was brought back to ZZZ and we did the best of our abilities.Suggestions: Maintenance just has to keep maintaining these airplanes even more better because if not more issues will be happening which is not good for the company. I brought the airplane back to ZZZ because let's say if we continued on and something else or more happened then what; so I decided to bring it back to a maintenance base which the QRH stated land at nearest airport.