Operation CHARM: Car repair manuals for everyone.

Fluorescent Leak Detectors

Tools Required:
J 41436 Tracer Dye Injector Tool
J 41 447 Fluorescent Tracer Dye

If the leak can not he found with J 39400 and the system is lo~own to have lost charge, a fluorescent leak tracer dye is available. This dye mixes with the R-134 PAG oil. This dye is detectable through the use of an ultraviolet light and glows yellow/green at the leak location.

Important
- J 41447 is the only approved dye by General Motors. Not all R-134 dyes are compatible with PAG oil. Some dyes decrease the oil viscosity or chemically react with the oil.
- PAG oil is water soluble and traces of PAG oil found at leaking joints are subject to washing out Condensation on refrigerant lines or the evaporator core may wash the PAG oil and leak dye off the line or off the core and out the condensation drain. This can make some leaks harder to find using the dye detector. Fluorescence at the drain opening would indicate a core leak.
- Use of the R-134 tracer dye requires time. Depending upon the leak rate, it may take between 15 minutes and 7 days for the leak to become visible.
- The dye, mixed with PAG oil, is retained in the system and is detectable for 2 years. Do not double the system with dye as this may cause reliability concerns. Use only the 1/4 once charge.

The dye has a refrigerant leak detection notice sticker included with the package. Complete the sticker information and place near the charge label.

Dye Injection

R-134 dye can be injected by two methods:

1. With the A/C system charged, use the instructions provided with the new R-134a leak dye injection tool J 41436.
2. With A/C system discharged, add dye into the new replaced component assembly.

After servicing an A/C component with dye, it is important to wipe the joint and access port clean of any residual dye to prevent false diagnosis at a later point.