Leak Testing
Refrigerant Leak Testing
Note: 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 a halogen leak detector, even though the A/C system contains fluorescent dye.
The only time 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.
| | Note: 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 colour 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 detection lamp. |
| • | To prevent false diagnosis in the future, thoroughly clean the residual dye from any area where leaks were found. Use a rag and an approved fluorescent dye cleaner. |
Fluorescent Dye Injection
Note: Use only fluorescent dye approved by General Motors.
| • | 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. |
| | Note: Do NOT overcharge the A/C system with dye. |
| • | 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. |
| • | To prevent false diagnosis, thoroughly clean any residual dye from the service port with a rag and an approved fluorescent dye cleaner. |
Halogen Leak Detector
Warning: 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 .
Note: Halogen leak detectors are sensitive to the following items:| • | Some adhesives used in the vehicle |
| • | Many solvents and cleaners |
| • | Windscreen washing solutions |
Clean and dry all surfaces in order to prevent a false warning. Liquids will damage the detector.
Note: 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 halogen leak tester.
| © Copyright Chevrolet. All rights reserved |
