Thanks for being here! Our son has a 1989 Caddy Deville and got the F49 code along with several cruise control codes (E39, E63 & E65). He called today saying one of the pulleys on the engine is not turning and he did have to add coolant (a gallon). At
To protect the vehicle's cooling system from overheating, the BCM commands the compressor clutch to disengage if the coolant exceeds 126 C (259 F). Also, if the A/C high pressure refrigerant temperature exceeds 93 C (200 F), the clutch is turned "OFF" to prevent refrigerant "blow-out." Code F49 is stored by the BCM whenever the clutch is being disengaged due to one of the above conditions. Customer complaints of "insufficiant cooling" or "engine overheating" may be associated with this code. If a hard or intermittent code F49 has been stored, the coolant and refrigerant systems must be investigated for the cause of a high temperature condition. Possible causes would include blockage in coolant flow, blockage in refrigerant flow or insufficiant air flow over radiator/condenser.
Check the coolant level, thermostat for operation. It sounds like it is running hot and it needs to be checked out by a shop.