Tools Required
Refrigerant Leak Testing
Important: General Motors vehicles are now manufactured
with fluorescent dye installed directly into the air conditioning (A/C) system.
The fluorescent dye mixes and flows with the polyalkylene glycol (PAG) oil throughout
the refrigerant system.
Verifying some passive leaks may require using the
J 39400-A
, even though the A/C system contains fluorescent dye.
The only time that adding additional fluorescent dye is required is after flushing
the A/C system.
Fluorescent Leak Detector
Fluorescent dye will assist in locating any leaks in the A/C system.
| | Important: PAG oil is water soluble.
|
| • | Condensation on the evaporator core or the refrigerant lines may wash the PAG
oil and fluorescent dye away from the actual leak. Condensation may also carry dye
through the HVAC module drain. |
| • | Leaks in the A/C system will be indicated in a light green or yellow color
when using the leak detection lamp. |
| | Use the leak detection lamp in the
following areas: |
| - | All fittings or connections that use seal washers or O-rings |
| - | All of the A/C components |
| - | The A/C compressor shaft seal |
| - | The A/C hoses and pressure switches |
| - | The HVAC module drain tube, if the evaporator core is suspected of leaking |
| - | The service port sealing caps |
| - | The sealing cap is the primary
seal for the service ports. |
| • | Follow the instructions supplied with the
J 42220
. |
| • | To prevent false diagnosis in the future, thoroughly clean the residual
dye from any area where leaks were found. Use a rag and the approved
J 43872
. |
Fluorescent Dye Injection
| | Important: Use only fluorescent dye approved by General
Motors.
| • | J 41447 can be poured
directly into a removed A/C component. |
|
| • | Not all of the fluorescent dyes are compatible with PAG oil. Some types of dye
decrease the oil viscosity or may chemically react with the oil. |
| • | R-134A leak detection dye requires time to work. Depending upon the leak
rate, a leak may not become visible for between 15 minutes and 7 days. |
| | Important: Do NOT overcharge the A/C system with dye.
Use only one 7.39 ml (0.25 oz) charge.
|
| • | To prevent false diagnosis, thoroughly clean any residual dye from the service
port with a rag and the approved fluorescent dye cleaner
J 43872
. |
Halogen Leak Detector
Caution: Do not operate the detector in a combustible atmosphere since its sensor
operates at high temperatures or personal injury and/or damage to the equipment
may result.
Ensure that the vehicle has at least 0.45 kg (1 lb) of refrigerant
in the A/C refrigeration system in order to perform a leak test. Refer to
Refrigerant Recovery and Recharging
for recharging the
A/C system.
Important: Halogen leak detectors are sensitive to the
following items:
| • | Windshield washing solutions |
| • | Many solvents and cleaners |
| • | Some adhesives used in the vehicle |
Clean and dry all surfaces in order to prevent a false warning. Liquids will
damage the detector.
Important: Follow a continuous path in order to ensure
that you will not miss any possible leaks. Test all areas of the system for leaks.
Follow the instructions supplied with the
J 39400-A
.
