Operation CHARM: Car repair manuals for everyone.

Vehicle Damage Warnings

Vehicles that use Refrigerant 134a (R-134a) in the A/C system have a caution plate attached to the rear wall of the engine compartment. Components designed solely for use with R-134a are marked accordingly, to distinguish them from components designed solely for use with Refrigerant 12 (R-12).

R-12 and R-134a systems require different types of lubricating oil. Components designed solely for use with one refrigerant and oil type must never be interchanged with components designed solely for use with another type of refrigerant and oil type.

R-134a differs entirely from R-12 in its composition, therefore, the two should never be mixed. Always charge system with correct amount of specified refrigerant.