Mercedes Benz automatic transmission Control Unit

The AMG SPEEDSHIFT 7G-TRONIC automatic transmission is electronically controlled and features three specially tailored shift programs which permit extremely sporty or comfort-oriented driving. The driver can select the shift programs by means of a selector button in the center console:
• C-mode (Comfort): Shift operations are performed at lower engine speeds for a comfort-oriented driving style
• S-mode (Sport): Shift operations are performed at higher engine speeds with quicker gear changes for a sporty driving style
• M-mode (Manual): Shift operations are triggered manually and with extremely short shift times using the steering wheel gearshift buttons
The fully integrated transmission control system offers the following benefits compared to conventional transmission control systems:
• Integration of all functions and components of the transmission in one installation module
• Module is integrated into transmission
• Minimization of interfaces with the wiring harness
The fully integrated transmission control unit (VGS) is installed in the oil pan of the automatic transmission.
It is continuously flushed with transmission oil to keep it cool.
The automatic transmission can be operated in three different ways.
The desired gear range can be engaged via:
• The selector lever in the center console (gear range "R" or "D")
• Manual shifting by actuating steering wheel gearshift buttons
• Manual shifting by pressing selector lever to left or right
The C 63 AMG is the first AMG vehicle to be equipped with an automatic positive torque function for downshifting.
This function provides for almost load-free downshifting, which also reduces load change reactions and is particularly beneficial when braking for oncoming curves (e.g. on race tracks).
Further advantages of the positive torque function include:
• Improved vehicle dynamics
• Improved driving safety
• Even quicker, load-free downshifting
• Reduction of braking torque on drive axle
· 1 Torque converter
· 2 Turbine wheel
· 3 Stator
· 4 Impeller
· 5 Transmission housing breather
· 6 Oil pump
· 7 Multidisk brake B1
· 8 Multidisk clutch K1
· 9 Ravigneaux gear set
· 10 Multidisk brake B3
· 11 Multidisk clutch K2
· 12 Simple planetary gear system
· 13 Multidisk brake BR
· 14 Multidisk clutch K3
· 15 Multidisk brake B2
· 16 Park pawl gear
· 17 Exciter ring for rpm sensing nout
· 18 Range selector lever
· 19 Ring magnet for rpm sensing n2
· 20 Shift valve housing
· 21 Ring magnet for rpm sensing nturb
· 22 Control solenoid valve
· 23 Force bridgeover with torsional damper elements
· Y3/8n4 Fully integrated transmission control (VGS) control unit
To prevent critical temperature peaks, the C 63 AMG is equipped with an auxiliary transmission cooler which is integrated in the upper area of the radiator module.
The transmission oil is pumped through the transmission cooler by the oil pump of the automatic transmission.
The transmission oil is heated or cooled as follows:
• At T < 80 °C it is heated so that the automatic transmission reaches its operating temperature more quickly
• At T > 80 °C it is cooled to prevent thermal overload
The auxiliary transmission cooler is equipped with a transmission oil thermostat.
At a transmission oil temperature of T < 80 °C, the transmission oil flows directly back to the automatic transmission via the return line.
At a transmission oil temperature of T > 80 °C, the transmission oil thermostat opens and the transmission oil flows through the transmission cooler before it flows back to the transmission through the return line.
Transmission oil cooling componants:
· 1 Auxiliary transmission cooler
· 2 Transmission oil thermostat
· 3 Radiator
· 4 Transmission oil cooler
· 5 Condenser
· A Feed to cooling circuit from transmission
· B Feed to transmission oil heat exchanger
· C Return from transmission oil heat exchanger
· D Feed to transmission oil thermostat
· E Return from transmission oil thermostat
· F Return from cooling circuit to transmission

AutoHex (Auto Diagnostic scanner) is one of the best Professional scan tools to for Mercedes Benz; Autohex Scanner can test Mercedes Benz Systems effectively and easily, with many powerful features to help you in diagnosing and testing. For more information:
Mercedes Benz Scan Tool

AutoHex II

Autohex II For BMW

AutoHex II For Kia and Hyundai

AutoHex stand alone

Mercedes Technical Info