Operation CHARM: Car repair manuals for everyone.
Manuals through 2025 now available!

Our trusted friends have launched a new website named LEMON, which has newer manuals. It also contains all the CHARM manuals.

LEMON is the spiritual successor to CHARM, I recommend you try it!

Link: lemon-manuals.la or lemon-manuals.org.ua

(Some people have issue connecting. LEMON is investigating. For now, use Firefox or change your DNS server)

Or, hide this message: temporarily or permanently

Identifying R-12 and R-134A Systems

IDENTIFYING R-134A AND R-12 SYSTEMS

NOTE: R-134a A/C systems can be identified by a gold colored A/C compressor clutch.

CAUTION: Do not add R-12 refrigerant to an A/C system that requires the use of R-134a refrigerant. Also, do not add R-134a refrigerant to an A/C system that requires the use of R-12 refrigerant. These two types of refrigerant should never be mixed. Doing so may cause damage to the A/C system.

R-134a A/C System Identification And Charge Tag Locations:






In order to find out which type of A/C system a particular vehicle has, the A/C system major components and refrigerant lines need to be inspected. If the system components have yellow R-134a NON-CFC tags as shown, it is an R-134a system requiring the use of R-134a refrigerant.

If the A/C system has any of the R-134a identifying characteristics explained, R-134a refrigerant is the only type of refrigerant that can be used in the A/C system. If the A/C system is not identified as an R-134a system as explained, it is an R-12 system requiring the use of R-12 refrigerant.