Most shifts are comprised of one clutch (or brake) being applied and another clutch (or brake) is being released (synchronous shift). As a reference, the time elapsed between each peak is 3.33 milliseconds.Įlectronic control over the entire pressure range of the transmission means that the TCM can ramp the rise and drop of pressure to specific clutches and brakes in order to achieve a smooth shift. Figure 2 below shows the signals applied to K1, K2, and K3 control solenoids on the tail-end of a 3-4 shift where the duty cycles are 12%, 40% and 60% respectively. The majority of pressure modulation occurs between 20 and 55% duty cycle. At 12% duty cycle the solenoid is essentially “off” which allows all input pressure to pass through a normally open solenoid. The solenoids are driven by signals that vary from 12-60% duty cycle with 60% being “fully energized,” limiting the normally open solenoid’s output to near 0 psi. Due to the variations in current draw depending on heat and specific resistance of the solenoid, measuring duty cycle percentage is a more consistent, accurate, and preferred representation of solenoid load. An accepted but ineffective aftermarket industry standard is to simply measure current being supplied to the solenoids to determine load. The linear solenoids are supplied 12V power in the form of a 300 Hz PWM signal. To understand how the linear solenoids control the engagement of the clutches and brakes, we must first understand the signal driving them. The detailed function of each solenoid and clutch is illustrated in Figure 1.įigure 1 09G Solenoid and Component Chart Operation of Solenoids During Shifts The two on/off solenoids are normally closed and are energized for various purposes including engine braking and torque converter lock-up. The TCC solenoid is normally closed and increases pressure output with increased current draw.
Five of the linear solenoids are normally open and function to reduce pressure output with increased current draw. The remaining two control line pressure and torque converter lock-up. Of the six linear solenoids, four of the units directly control clutches and brakes via spring loaded spool valves in the valvebody. The 09G has six linear solenoids and two on/off solenoids. The 09G will be the specific focus of the article although most of the information holds true for the 09D (TR60), TF80, and TF81.įirst, let’s examine the solenoids and their role in the transmission.
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This article will dissect exactly what is happening during select shifts and how to make adjustments to the valvebody in order to obtain the desired level of drivability.
Whenever any conditions change within the hydraulic circuit, such as the valvebody or solenoids, adjustments to the system may be necessary. With this improved system, the TCM has more ability to adapt and precisely control the quality of shifts but ultimately the control is limited.
The following is a summary of that research:Īisin-Warner has made several improvements related to the operation and design of this 6-speed family relative to earlier 5-speed (AW55-50) family, including the utilization of dedicated linear solenoids to directly control clutches. The experts at Rostra have devoted a substantial amount of effort to determine how all of the aspects of Aisin 6-speed transmissions (valvebody, solenoids, and TCM) work together to provide a good functioning and durable transmission repair. Once a repair had been made, shift or apply issues still existed at times requiring more attention to the controls. Much focus has been spent over the years on valvebody wear issues and other deficiencies of the 09G as well as the TF80 / TF81 models. Its close cousins, the TF80 (Volvo and GM) and TF81 (Ford and Mazda) further enhance a huge market potential for the transmission repair industry. The 09G can be found in a variety of Volkswagen FWD vehicle platforms produced after 2003. The Aisin-Warner 09G six speed FWD transmission, or TF-60, has increased in popularity and technicians need to become more familiar with all aspects. Aisin-Warner 09G Electronics – Anatomy of Shift Controls