To locate a red, oily fluid leak under a vehicle with an automatic transaxle, what method does a technician use?

To locate a red, oily fluid leak under a vehicle with an automatic transaxle, performing a dye test is an effective method. The dye test involves adding a fluorescent dye to the automatic transmission fluid. When the vehicle is run, any leaks will allow the dyed fluid to escape and become visible. Under a UV light, the dye will glow brightly, making it much easier for the technician to pinpoint the exact location of the leak. This method is beneficial as it enhances visibility of the fluid, especially in areas where it may be difficult to see standard transmission fluid.

While inspecting fluid levels is important for overall transmission health and could indicate a leak if levels are low, it does not provide direct evidence of where the leak is occurring. Checking for leaks when idling might reveal some leaks, but it may not be comprehensive, as fluid might only leak under pressure or during vehicle operation. A pressure test can help diagnose internal leaks but is not specifically designed to identify external leaks under the vehicle. Therefore, using a dye test is the most direct and effective method for locating red, oily fluid leaks from an automatic transaxle.