Using UV Light (Black Light)
1. Remove on the engine or transaxle.
Note
2. Pour the fluorescent dye into the engine oil or ATF (or transaxle oil).
3. Allow the engine to run for 30 minutes.
4. Inspect for dye leakage by irradiating with UV light (black light), and identify the type of oil that is leaking.
5. If no dye leakage is found, allow the engine to run for another 30 minutes or drive the vehicle then reinspect.
6. Find where the oil is leaking from, then make necessary repairs.
Note
Not Using UV Light (Black Light)
1. Gather some of the leaking oil using an absorbent white tissue.
2. Take samples of engine oil and ATF (or transaxle oil), both from the dipstick, and place them next to the leaked oil already gathered on the tissue.

3. Compare the appearance and smell, and identify the type of oil that is leaking.
4. Remove any oil on the engine or transaxle/transmission.
5. Allow the engine to run for 30 minutes.
6. Check the area where the oil is leaking, then make necessary repairs.
Special service tools
Disconnection of the negative battery cableMazda 6 Service Manual: Foreword
When the customer reports a vehicle malfunction, check the malfunction
indicator lamp (MIL) indication and diagnostic trouble code (DTC), then
diagnose the malfunction according to following flowchart.
- If a DTC exists, diagnose the applicable DTC inspection. (See DTC
TABLE.)
- ...
Mazda 6 Service Manual: Dual proportioning valve inspection (without abs)
1. Connect the SSTs to the brake pipes as shown in the figure.
2. Bleed the air from the brake system.
3. Measure the fluid pressure of the master cylinder and the rear brake.
If not within the specification, replace the dual proportioning valve.
Fluid pressure
...