Citation Excel (C560XL)
Flight Crew Air Transport Pilot (ATP)
Troubleshooting
Aircraft Equipment Problem Critical
Flight Crew Returned To Departure Airport; Flight Crew Landed in Emergency Condition
Aircraft
Climbing out; EMERG PRESS ON came on; ran checklist; unable to fix; [advised ATC]; landed.
Climbing out of ZZZ; EMERG PRESS ON light came on; ran checklist; wouldnt turn off; [advised] ATC; landed back at ZZZ.
Citation flight crew reported experiencing pressurization malfunction after takeoff.