Refrigerant System Dye

Fluorescent refrigerant system dye is added to the refrigerant system at the factory to assist in refrigerant system leak diagnosis using a Rotunda-approved UV blacklight. It is not necessary to add additional dye to the refrigerant system before diagnosing leaks, even if a significant amount of refrigerant has been removed from the system. Additional refrigerant system dye should only be added if more than 50% of the refrigerant system lubricant capacity has been lost due to a fitting separation or hose rupture. Refer to CLIMATE CONTROL SYSTEM - GENERAL INFORMATION & DIAGNOSTICS -- FUSION, MILAN & MKZ (EXCEPT HYBRID) article.

For hybrid vehicles equipped with an electric compressor, additional refrigerant system dye should only be added by installing a new receiver/drier cartridge. Replacement receiver/drier cartridges include a fluorescent dye "wafer" which will dissolve after approximately one hour of continued A/C operation. Fluorescent refrigerant system dye mixed with PAG oil should never be used in hybrid vehicles with an electric A/C compressor.