722.6 Transmission Control

722.6 Transmission Control

How we are different from other tcu’s on the market. We model and simulate a variety of automotive systems using Simulink. We can model and simulate the vehicle and environment, and develop control algorithms for automotive applications and 722.6 5g control firmware changes with Factory A2L libraries we use, not some incomplete information you find on some automotive file dump sites and go in and edit not defined calibration libraries and or use hex editor and not even know how firmware functions let alone how transmission and valve body function and send out for the public to test and cause possible damage to transmission components.

What is a A2l?

It contains all information about the relevant data objects in the TCUsuch as parameters, maps, real and virtual measured variables, structures, and variant dependencies.

OEM Mercedes TCU will be shipped to you, not some home brew custom-made low-quality knockoff tcu’s that have been marketed on youtube with non-automotive-grade components. We don’t reinvent the wheel, we make it better using OEM hardware and Recalibrated OEM Firmware.

EGS52 TCU is NOT Vin Coded! They are SCN coded per chassis. E55 TCU Will NOT work in S55/SL55 you get a no start. Make sure you choose the correct version for your car.

Warning: This is a plug-and-play tcu! Do not use Star/ScanTool to transfer Tcu or change coding. It will put tcu calibration tune back to default!

Blue Top Solenoids Vs Brown Tops? Brown Tops = Poor Performance

Blue top solenoid higher fluid flow results in higher pressure that produce shorter shift events during part throttle operation that gives more firm faster shifts part throttle than old obsolete brown tops, tcu tunes work for brown tops but performance won’t be at peak level compared to Blue Tops and shifts per gear might not feel exactly the same.  The majority of 2005-2006 722.6 transmissions have blue-top solenoids stock, Most all V12 cars came stock with them 722.649 trans. Some older 03 04 cars had transmissions replaced due to radiator issues and got updated transmissions with blue-tops. When you change out the conductor plate is when you can see if you have blue or brown/black solenoid tops.

If you have brown tops my calibrations still work but won’t be the greatest as PWM tables are set for blue tops. For best performance is to upgrade them to blue tops. SLR tcu will still work with brown-tops but performance will be degraded until you upgrade. All m113k Cars need blue top solenoids. Browntops help calm down 150% valve body is the only time they are any good to use.

Changes that are made with tcu tunes:

We don’t make just 1 or 2 changes to calibrations and call it tuned and the car drives exactly the same as stock tcu.

Torque Modeling Overhauled.

(New Feature) Shift Points per throttle % and Kph/Mph have been changed. More sensitive downshifting in all modes and gears with less throttle.

WOT shift points have been raised to 6300 up from 6100 rpm which you can request higher WOT shift points but not recommend unless you have supporting mods (Gears 3.06, Cams, 3000 Stall, etc.) Shifting at 6700 that others set tcu at puts you out of the “M113k” power band=Slower Car.

K1,K2,K3,B1 clutch pressure adders have been calibrated along with overlap times, torque phase pressures, and more depending on what tune version is chosen.

Driving Factor Gear Box Learning Changed.

Torque Limiters per gear have been calibrated higher.

Full M-Mode Available which only works in M-Mode and does not auto upshift or downshift at WOT, holds gears and will hit the rev limiter until you manually shift.

Downshift Torque Limits have been modified to feel faster and less delayed as in closest you’re going to get without needing rev-matching.

M-Mode shifting is considerably faster than stock with less delay.

Tcc calibrations changed depending on tune level.

Transmission power control solenoid current values are set for blue top shift solenoids and values work fine for browntops but there will be a slight delay into drive and reverse but blue top shift solenoids are recommended for best performance.

Stages of tunes:

Stock Plus+ : Daily driver tune. Noticeable drivability changes due to many recalibration areas that are changed.

Stage 1 : Street Race Car to Daily Driver you will feel sports car type shifts that are nice and quick and wot fast quick shifts with considerably less delay in m-mode.

Stage 2 : Drag Car, High-Performance Racing, Max Performance From TCU before you need valve body upgrade for cars above 800hp. Not for the daily street-driven cars unless you like firm shifts at all speeds.

*Ultimate Stage X: Mercedes-Benz McLaren SLR Tcu Custom Software For E55/CLS55 AMG. Best tcu tune you can get without valve body modification*.

This uses base SLR Firmware but has been majorly overhauled. Stock SLR software does not function properly for street driving for E55/CLS55 AMG.  So there had to be some major changes to transmission control flow for TCC and many other calibrations from clutch pressures to gearbox learning and also shift points from low to midpoint throttle and coasting downshifts come into lower gear sooner no more lugging high gear all the time. The final outcome has been achieved with results that have exceeded expectations. Blue Top Solenoids Required for best shift speed and feel. . Most M113k AMG cars have them but some still rolling around with brown top solenoids that have lower pressure and flow which is recommended to swap out as they are obsolete. This is how all m113k cars should have shifted like from the factory. Perfect for daily driver to race applications.

Transmission mode meanings:

S- Sport

W/C- Winter, Comfort. 2nd gear starting

M- Manual Mode

A- Agility mode

Agility Mode= It uses the car’s built-in accelerometer and when it sees enough side loading on cornering it sets the tcu in A mode active. Rpm stays above 2000 and shifts get faster and throttle response sharper. Sport+ mode of sorts. A few older benz 03-04 won’t show A mode even when coded, Most likely due to ESP Module in older cars. Some older 03 cars will show A mode but will act like S mode.

One of the difficulties a transmission technician faces when working with a 722.6 transmission is the absence of pressure taps. Hydraulic pressures are calculated from input signals such as engine torque, engine speed, accelerator pedal position, cruise-control request, wheel speed, traction status, kick-down switch, selector-lever signal, and the program-select switch C/M/S/A. The TCM uses these inputs to achieve proper shift timing and shift feel under diverse driving conditions through four basic adaptation programs: driving style, shift time, fill pressure and fill time.

Computer Strategy

The TCM uses these inputs to achieve proper shift timing and shift feel under diverse driving conditions through four basic adaptation programs: driving style, shift time, fill pressure and fill time. Also, ECU tunes and Engine mods will change the torque curve of the engine and we scale pressure curves and other calibrations so more torque output scales shifts to be more aggressive the more torque output engine makes.

Driving Style 

This program is ready to adapt to the driving condition as it happens. The TCM constantly monitors vehicle speed and throttle opening as well as the rate of change of the throttle as it opens and closes. It also looks at lateral acceleration, which is a term for curve recognition. Basically, it monitors wheel speeds to determine when the vehicle is in a turn. In addition to these inputs, it also monitors the frequency of gear changes. As a result, it can adapt quickly to a shift time and feel appropriate for the present condition. This adaptation, not written to memory, is known as an adaptation that “lives for the moment.”


Shift Time (Shift Overlap)

This strategy focuses on the quality of the upshifts and downshifts under both load and no-load conditions. Shift-time adaptation gives the TCM the ability to electronically alter the time it takes to go from one gear to another; in other words, the time it takes to disengage one clutch while applying another. Once the TCM has calculated the type of shift that needs to take place, the TCM uses the following two strategies to accomplish the task.


Fill Pressure (Apply Pressure)

This strategy gives the TCM the ability to control and modify the pressure used to engage a clutch, which results in the type of shift feel that will occur.* This is where the SAG 150% valve body does this by modifying valve body to raise pressures above what is originally calculated in software so pressures are higher than what is stock means faster clutch ramp rates and more clamping pressure which is good for higher hp/tq cars.*



Fill Time (Preload Pressure)

This strategy gives the TCM the ability to control the time it takes to fill a clutch drum, bringing the clutch pack to a zero clearance but not yet applying the clutch. This adaptation compensates for wear of the friction plate. The K2 Clutch pack is the weak link in the 722.6 and most of the time the first to wear out due to many variables as an example never doing fluid services, running low on fluid, going past known max torque levels of the 722.6 without upgrades to clutches, high mileage wear.

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