This bulletin applies to 2008-2015 Mitsubishi Lancer Evolution and 2009-2015 Lancer Reliant vehicles. In the case of difficulty bleeding the Active Yaw Control/Active Centre Differential (AYC/ACD) system, the applicable Mitsubishi service manual correctly describes the bleeding procedure necessary when replacing the AYC/ACD hydraulic pump or related components. However, if the system is not properly bled, unusually loud noises will be heard when the pump operates.
A heavy click/clunk noise can be heard after starting the engine and depressing the brake pedal or while the brake pedal is depressed and the engine is then started. The clunk is due to air being trapped in the AYC/ACD system. Continue bleeding until the noise is eliminated.
Automatic transmission fluid (ATF) may not be filling the area below the filter in the AYC/ACD reservoir. If the bottom third of the reservoir is not filled with fluid after pouring ATF into the reservoir, squeeze the large inlet hose several times. This will help displace the trapped air and fill the lower third of the reservoir prior to bleeding the system. It is recommended that you remove the inner trunk panel to view the reservoir.
If you encounter a negative message from MUT3 SE while attempting to start the bleeding procedure, check the steering wheel position. The steering wheel must be at the straight-ahead position for the activation procedure to begin.
Note the area below the filter where air may be trapped.