GF00.20>W>3005H Reset service item function 2.8
OUTPUT DATA
5.5 IC control unit (ICUC) (A1)
The IC (ICUC) control unit (A1) shows the driver information over the multifunction display (A1 p1).
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
6 Transmission cooling (for code N6Z)
A thermostatically regulated transmission cooling with the following components is used as special equipment:
f Transmission cooler with a transmission cooling fan (M19) (located in the direction of travel on the right, next to the cooling module)
f Transmission oil lines
f Thermostat element with spring from the shape memory alloy (FGL)
For transmission oil temperatures above 80∞C the spring force of the spring closes the cooler protection valve (bypass). The transmission oil flows through the transmission cooler and is cooled by the airstream.
If the transmission oil temperature increases further, the transmission cooling fan (M19) located on the transmission cooler is switched on from 90∞C over the SCA (SCA) control unit (A7). For transmission oil temperatures below 80∞C the spring opens the cooler protection valve. The transmission oil flows uncooled over the bypass back into the transmission.
i In the case of an excessively high transmission oil pressure the cooler and the transmission protection valve open and allow the oil to flow uncooled over a bypass back into the transmission.
Overall network for transmission automation
Page 40
Operation, function
Page 41
Driver information, function
Page 44
Transmission mode, function
Page 45
Shifting the transmission, function
Page 46
Controlling the clutch, function
Page 52
GF26.21>W>0002>01H Overall network for transmission automation
W26.00>1032>79
A1 Instrument cluster (ICUC) control unit
A2 Central gateway control unit (CGW) A3 Drive control (CPC) control unit A4 Engine management control unit
(MCM)
A5 Transmission control (TCM) control unit
A10b Electronic brake system (EBS) control unit
S23 Right multifunction control lever S110 Left multifunction steering wheel
button group
S111 Right multifunction steering wheel button group
Z1 Cab instrument panel CAN bus star point
Z3 Frame CAN bus star point Z4 Drive CAN bus star point A10c Electronic brake system (EBS)
control unit
A43 Modular switch panel (MSF) control unit
CAN 2 Interior CAN CAN 3 Frame CAN CAN 4 Drive train CAN
LIN 3 Multifunction control lever>LIN on the right
LIN 7 Button group LIN P1 Tachograph (TCO)
GF26.21>W>3003H
Operation, function
2.8.11
TRANSMISSION 715 in MODEL 963 with CODE (G5G) Mercedes PowerShift 3
TRANSMISSION 715 in MODEL 964 with CODE (G5G) Mercedes PowerShift 3
W26.21>1119>06
A3 Drive control (CPC) control unit A5 Transmission control (TCM) control
unit
CAN 4 Drive train CAN
LIN 3 Multifunction control lever>LIN on the right
S23 Right multifunction control lever S23s1 Transmission position switch
(D/N/R)
S23s2 Gearshift paddle (+/>)
S23 s3 Transmission mode (M/A) button
Normal operation
The shift commands are recorded over in the integral controls in the RH multifunction control lever (S23):
f Transmission position (D/N/R) switch (S23 s1) f Gearshift paddle (+/>) (S23 s2)
f Transmission mode (M/A) button (S23 s3)
The drive control (CPC) control unit (A3) reads in the shift signals from the RH multifunction control lever (S23) via the RH multifunction control lever LIN (LIN 3), evaluates them and sends appropriate CAN messages to the transmission (TCM) control unit (A5) via the drive train CAN (CAN 4).
Twelve forwards gears, 4 reverse gears and neutral can be engaged.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
Automatic operation
(the optimal gear (the required gear specification) is determined by the drive control (CPC) control unit (A3))
Gear selection is dependent on the following influencing variables:
f Ground speed (only relevant for the start>off gear) f Accelerator pedal position (specified torque) f Load condition of engine
f Operating point of the target gear f Starting speed of the transmission f Operation of the permanent brake f Load condition of the vehicle f Shift program
f Lay of the land for the driving lane
Manual mode
Difference to automatic mode:
f The shifting operations must be initiated by the driver, that is the driver determines the shift point and shift direction. f The kickdown function is not available.
Operation of the driving functions
The driving functions assist the driver in daily driving to drive with a more fuel economy. They increase the ride comfort and support him in difficult situations.
Selectable driving functions are:
f EcoRoll mode,in certain driving situations for supporting a fuel>saving driving style through automatic shifting into the transmission neutral position "N" when the accelerator is not actuated
f Rocking mode,for rocking the vehicle out of an off>road recess
f Crawl mode, for automatic starting moving when releasing
the service brake and continued crawling without actuating the accelerator pedal.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
EcoRoll mode Preconditions
f EcoRoll function activated
f Ground speed was > 35 km/h and is > 25 km/h (hysteresis) f Accelerator not operated
f Service brake or permanent brake not actuated f Driver assistance systems not in control mode f Brake assistant systems not in control mode f Power take>off switched off
f Variable speed limiter maximum speed not exceeded f CC speed tolerance not exceeded
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
Function sequence
If the pre>conditions are fulfilled then the drive control (CPC) control unit (A3) requests the neutral position from the
transmission (TCM) control unit (A5) via the drive train CAN (CAN 4). The transmission (TCM) control unit (A5) actuates the
transmission positioner (Y900) to open the clutch. After successful opening of the clutch, read in over the clutch position sensor (B503), the transmission positioner (Y900) is actuated to engage neutral. After ending the switching the transmission (TCM) control unit (A5) transmits the engaged neutral to the drive control (CPC) control unit (A3) via the drive train CAN (CAN 4). i Based on the reduced engine speed a somewhat lower steering assist can occur and therefore greater steering forces in certain driving situations, for example on slightly curved downslopes. The operation or road safety is not endangered by this.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
Crawl mode
The crawl function is always switched on after an engine start and is activated after first moving off.
The crawl function is deactivated under the following conditions: f The crawl function is switched off over the IC (ICUC) control
unit (A1)
f The transmission in neutral for longer than 2 s f The parking brake is tightened
f The rocking mode is activated
f Driver assistance systems switch into control mode f Idle speed > 700 rpm
f Threat of clutch overloading
f An excessively high air drag and rolling resistance f An excessively high tire grip
i The crawl function is similar in its behavior to an automatic torque converter. Since the function is realized over the clutch the function is not wear>free and the vehicle in the slip range of the clutch is not capable of permanently crawling.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
Function sequence
The crawl function consists of 2 parts:
f In gears 1 to 6, R1 and R2, self>actuated starting crawling by releasing the service brake (only for an active crawl function) f In gears 1 to 6, R1 and R2 further crawling (=freewheeling)
for a non>actuated accelerator pedal
The driving off dosing occurs for first driving off over the accelerator pedal. The system is taught in in the process to the torque prescribed by the driver. After the first "real" driving determination of the crawling torque depends on the determined vehicle mass and incline in the driving lane.
i If driving with a trailer is recognized over the trailer recognition the mass and incline dependent crawling torque is reset in the drive control (CPC) control unit (A3) and teaching in occurs again during first driving off.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
Rocking mode Function sequence
Rocking mode is activated over the rocking mode button (S938). If rocking mode has been activated the transmission control changes from automatic into manual mode.
Accelerator pedal requests are implemented more directly and the clutch is opened more rapidly for a non>actuated accelerator pedal. The clutch is closed quickly again as soon as the accelerator pedal is actuated again. Through repeated actuation and release of the accelerator pedal can put the vehicle into a rocking mode condition and in this way can rock the vehicle free out if a hollow.
Back>up mode
Back>up mode represents a last emergency function for engaging gears for a vehicle standstill. The operating commands for navigation are entered in the menu tree multifunction display (A1 p1) in the IC (ICUC) control unit (A1) over the LH multifunction steering wheel button group (S110) and the RH multifunction steering wheel button group (S111).
The modular switch panel (MSF) control unit (A43) reads in the switching commands from the LH multifunction steering wheel button group (S110) and the RH multifunction steering wheel button group (S111), evaluates them and transmits appropriate CAN messages via the interior CAN (CAN 2), the central gateway (CGW) control unit (A2) and the frame CAN (CAN 3) to the drive control (CPC) control unit (A3).
The drive control (CPC) control unit (A3) evaluates the switching request from the driver, determines the targeted gear to be switched and, for release, transmits appropriate CAN messages via the drive train CAN (CAN 4) to the transmission (TCM) control unit (A5).
The following switching positions can be selected in back>up mode:
f R (for reverse gear) f N (for neutral) f D1 (for 2nd gear) f D2 (for 6th gear)
f Towing (for the towing mode)
The actuation of the clutch is controlled automatically as long as no malfunction is present. A malfunction would result in automatic clutch operation being disabled.
i If gear selection was not enabled, a shift to "neutral" is always enabled.
Instrument cluster control unit (ICUC), component description
A1
Page 331
Component description for central gateway control unit (CGW)
A2
Page 333
Component description for drive control (CPC) control unit
A3
Page 334
Component description for transmission control (TCM) control unit
A5
Page 337
Component description for modular switch panel control unit (MSF)
A43
Page 370
Component description for right multifunction control lever
S23
Page 463
Component description for multifunction steering wheel
GF26.21>W>3005H
Driver information, function
2.8.11
TRANSMISSION 715 in MODEL 963 with CODE (G5G) Mercedes PowerShift 3
TRANSMISSION 715 in MODEL 964 with CODE (G5G) Mercedes PowerShift 3
W26.21>1118>76
A1 Instrument cluster (ICUC) control unit
A1 p1 Multifunction display
A3 Drive control (CPC) control unit A5 Transmission control (TCM) control
unit
B50 Center speaker CAN 3 Frame CAN CAN 4 Drive train CAN
Displaying shift status
The drive control (CPC) control unit (A3) transmits the information for indication of the switching condition to the IC (ICUC) control unit (A1) via the frame CAN (CAN 3).
To do this the transmission (TCM) control unit (A5) permanently transmits the CAN messages with information about the condition of the transmission (for example the engaged gear, the possible gear) to the drive control (CPC) control unit (A3) via the drive train CAN (CAN 4). Before execution of the shift operation the drive control (CPC) control unit (A3) transmits the targeted gear request (determined from the automatic gear selection or the gear selected by the driver) to the transmission (TCM) control unit (A5). The transmission (TCM) control unit (A5) transmits the confirmed targeted gear and the engaged current gear to the drive control (CPC) control unit (A3) .
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
The IC (ICUC) control unit (A1) receives the CAN messages and generates the following displays in the multifunction display (A1 p1):
f display of the direction of travel and / or the engaged gear f display of the gearshift recommendation or to engaged gear f display of the transmission mode
The previous display is retained during the shift operation. The current display only takes place when the shift operation is concluded.
i During the teach>in process appropriate CAN messages are transmitted with information for display of the active teach>in process. Also in back>up mode all CAN messages are transmitted, as in normal mode, via the drive control (CPC) control unit (A3) and the frame CAN (CAN 3) to the IC (ICUC) control unit (A1). >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
Emit warning tones acoustically
The transmission (TCM) control unit (A5) transmits CAN messages with information concerning the condition of the transmission (for example on the switched gear, the possible gear, temperature of the transmission oil) to the drive control (CPC) control unit (A3) via the drive train CAN (CAN 4).
The drive control (CPC) control unit (A3) decides over a warning emission to the driver. If a warning emission is necessary, the drive control (CPC) control unit (A3) transmits an appropriate CAN message with the information for output of warning tones to the IC (ICUC) control unit (A1) via the frame CAN (CAN 3).
The IC (ICUC) control unit (A1) receives the CAN messages from the drive control (CPC) control unit (A3) and generates acoustic messages whose output takes place over the center speaker (B50).
Component description for instrument cluster control unit (ICUC)
A1
Page 331
Component description drive control (CPC) control unit
A3
Page 334
GF26.21>W>3007H
Transmission mode, function
2.8.11
TRANSMISSION 715 in MODEL 963 with CODE (G5G) Mercedes PowerShift 3
TRANSMISSION 715 in MODEL 964 with CODE (G5G) Mercedes PowerShift 3
General information
One can select between a manual transmission mode (manual operation) or an automatic transmission mode (automatic operation). In automatic operation there is a standard switching program (A) and either the shift program (A power) or the shift program
(A economy) available depending on the vehicle and transmission design.
Automatic transmission mode
The transmission automation is fitted with a standard shift program:
f A, with kickdown, accelerator pedal curve standard, CC
standard, maximum speed of 89.8 km/h, function EcoRoll which can be switched off
The driving specific shift programs have the following significant properties:
f A power, switchings take place at an about 100 rpm higher
rotational speed in comparison with a standard shift program and dynamic clutch matching for driving off f A economy, no kickdown possible, EcoRoll cannot be
switched off, maximum speed of 85 km/h, accelerator pedal curve and max. engine torque lowered, CC Softcruise i Selection of the automatic transmission mode takes place over the transmission mode button (M/A) (S23 s3) on the RH
multifunction control lever (S23).
Manual transmission mode
In manual transmission mode the shift operations are initiated by the driver over it. This means that the driver determines the shift point and the switching direction. The kickdown function is not available.
Component description for right multifunction control lever
GF26.20>W>3007H
Shifting the transmission, function
2.8.11
TRANSMISSION 715 in MODEL 963 with CODE (G5G) Mercedes PowerShift 3
TRANSMISSION 715 in MODEL 964 with CODE (G5G) Mercedes PowerShift 3
W26.21>1123>09
Schematic representation
1 Gate cylinder
2 Range group shift cylinder 3 Gear cylinder
4 Splitter group shift cylinder 6 Countershaft brake 6.1 Mechanical vent valve
7 Pneumatic central clutch release bearing
A1 Instrument cluster (ICUC) control unit
A2 Central gateway control unit (CGW)
B504 Range group travel sensor CAN 2 Interior CAN
CAN 3 Frame CAN CAN 4 Drive train CAN
LIN 3 Multifunction control lever>LIN on the right
LIN 7 Button group LIN
S23 Right multifunction control lever S110 Left multifunction steering wheel
button group
S111 Right multifunction steering wheel button group
A3 Drive control (CPC) control unit A4 Engine management (MCM)
control unit
A5 Transmission control (TCM) control unit
A43 Modular switch panel (MSF) control unit