This TSB article is being republished in its entirety to update the text.
Ford Motor Company now produces new vehicles with R-134a fluorescent tracer dye incorporated into the A/C system and spring lock couplings which contain three (3) O-rings.
Leak checking can be performed with the use of a Rotunda UV Lamp (112-R0021) and is an acceptable alternative to using an electronic leak detector.
Ford Motor Company has begun implementation of spring lock couplings with three (3) O-rings which provide an improved seal. Field and laboratory tests have shown a 40% improvement in sealing capability and durable life.
Through field and fleet testing and analysis, it is apparent that lubricating oil used in vehicle assembly processes is easily misdiagnosed as a refrigerant leak. The presence of oil at connections is not necessarily an indication of a leaking connection. If oil at a fitting is due to a leak, fluorescent tracer dye will be present at the location. Any oil escaping from the A/C hoses will contain dye.
When checking for leaks, be sure to scan all components, fittings and lines of the A/C system with the UV lamp. The exact location of the leak or leaks can be pinpointed by the bright yellow-green glow of the tracer dye. Since more than one leak may exist in the system, always inspect each component.
The best leak detection results will be achieved in conditions of low ambient light. In areas that cannot be reached by the UV lamp: (1) use a technician's mirror or (2) use a non-fluorescent shop towel, wipe the suspected area, and then check the towel with the UV lamp for traces of the dye.
After the leak is repaired, the traces of dye can be removed from the previously leaking areas by using any general purpose oil solvent.
Verify the repair by operating the A/C system for a short while and reinspecting the system with the UV lamp.
BEGINNING WITH VEHICLES PRODUCED IN MAY 1996, THE TRACER DYE'S FLUORESCENT LIFESPAN IS THE LIFE OF THE VEHICLE. VEHICLES PRODUCED BEFORE MAY 1996 CONTAIN A TRACER DYE WITH A LIFESPAN OF ROUGHLY 500 HOURS OF A/C SYSTEM USE, AFTER WHICH TIME ANOTHER INFUSION OF DYE WOULD BE REQUIRED. REFER TO TSB
95-21-4 IF ADDITIONAL TRACER DYE OR INFORMATION IS REQUIRED.