Shown on rear axle differential |
6 | Multidisk clutch |
8 | Rear axle differential |
10 | Oil pump |
Y68/3 | All-wheel drive solenoid valve |
P35.30-2154-76
Sectional view of rear axle differential |
Pfeil | Direction of travel |
10 | Oil pump |
11 | Pressure chamber |
12 | Piston |
P35.30-2156-76
On vehicles up to model year 2016 and irrespective of the equipment specification, only one chassis CAN is available.
On vehicles as of model year 2016, there are two chassis CAN variants depending on the equipment installed.
Variant 1
If the vehicle has none of the equipment codes named in variant 2, 2016 only one chassis CAN (CAN E) is available.
Variant 2
If the vehicle has one of the following equipment codes, there are two chassis CANs (chassis CAN 1, chassis CAN 2) (CAN E1, CAN E2) present:
Code 218 (Reversing camera)
Code 234 (Blind Spot Assist)
Code 459 (Steel suspension with adjustable damping)
Code 475 Tire pressure monitor
Code 476 (Lane Keeping Assist)
Code 513 (Speed Limit Assist)
Code 614 (Bi-xenon headlamps)
Code 615 (Bi-xenon headlamps with active curve lights)
Code 618 (Bi-xenon headlamps)
Code 621 (Intelligent Light System (left-hand traffic))
Code 622 (Intelligent Light System)
Code 631 (Static LED headlamps for left-hand traffic system)
Code 632 (Static LED headlamps for right-hand traffic system)
Function requirements for 4MATIC rear axle differential, general
Internal combustion engine running
Drive train operational
The following signals are processed by the all-wheel drive control unit (N45):
Status of brake light switch (S9/1)
Wheel speed signals of rpm sensors (L6/1 - L6/4)
Signal of steering wheel angle sensor (N49)
Status of automatic transmission mode button (S16/12) (without code B59 (DYNAMIC SELECT))
Status of DYNAMIC SELECT switch (N72/1s3) (with code B59 (DYNAMIC SELECT))
Status of transmission mode rotary switch (S192) (in model 117.352/952, 156.952, 176.052, as of model year 2016)
Status of transmission control and 4MATIC control, request from dual clutch transmission fully integrated transmission control unit (Y3/14n4)
The following solenoid valve is actuated by the all-wheel drive control unit:
All-wheel drive solenoid valve (Y68/3)
4MATIC rear axle differential, general
The rear axle differential is designed as a single-speed differential. The housing of the rear axle differential is made of aluminum and is screwed on to the assembly carrier of the rear axle. The multidisk clutch is installed in the rear axle differential housing in order to enable rear axle switch-in. The multidisk clutch shares the oil supply source with the rear axle differential. The oil pump in the rear axle differential generates an increased oil flow if there is an rpm difference between the wheels on the front axle and the rear axle.
The all-wheel drive control unit receives the individual wheel speeds from the Electronic Stability Program control unit (N30/4) via the chassis CAN (in variant 1) or via chassis CAN 1 (in variant 2), the CDI control unit (N3/9) (with diesel engines) or the ME-SFI control unit (N3/10) (with gasoline engines) and via the drive train CAN (CAN C). In addition, the signal is sent to the dual clutch transmission fully integrated transmission control unit.
The all-wheel drive control unit uses this to calculate the rpm difference between the front axle and the rear axle. The all-wheel drive control unit also receives further signals such as, e.g. the steering wheel angle and the yaw rate. The steering wheel angle is transmitted by the steering column tube module control unit (N80) via the chassis CAN (in variant 1) or chassis CAN 1 (in variant 2), the CDI control unit or the ME-SFI control unit and the drive train CAN to the all-wheel drive control unit. The yaw rate is transmitted as the ESP® status by the Electronic Stability Program control unit via the chassis CAN (in variant 1) or chassis CAN 1 (in variant 2), the CDI control unit or the ME-SFI control unit and the drive train CAN to the all-wheel drive control unit. The Electronic Stability Program control unit transmits the status of the brake light switch via the chassis CAN (in variant 1) or chassis CAN 1 (in variant 2), the CDI control unit or the ME-SFI control unit and the drive train CAN to the all-wheel drive control unit and the dual clutch transmission fully integrated transmission control unit.
Depending on the driver's commands and the driving situation, a variable drive torque is generated by the rear axle differential. The drive torque at the multidisk clutch varies between 0 and 750 Nm. For this purpose, the all-wheel drive solenoid valve regulates the level of the oil pressure that acts on the piston and actuates the multidisk clutch. The torque transfer thus starts.
The all-wheel drive control unit transmits the status of the 4MATIC control and the request "Torque reduction/ESP® dynamics" via the drive train CAN, the CDI control unit or the ME-SFI control unit and the drive train CAN to the dual clutch transmission fully integrated transmission control unit. The request "Torque reduction/ESP® dynamics" is also transmitted via the chassis CAN (in variant 1) or chassis CAN 1 (in variant 2) to the Electronic Stability Program control unit.
The dynamics of the all-wheel drive are influenced by the transmission mode. The transmission mode is selected using the automatic transmission mode button (without code B59 (DYNAMIC SELECT)) or the DYNAMIC SELECT switch (with code B59 (DYNAMIC SELECT)). The corresponding status is read in directly by the upper control panel control unit (N72/1). The upper control panel control unit transmits the request via the battery sensor LIN (LIN B15), the SAM control unit (N10), the interior CAN (CAN B), the electronic ignition lock control unit (N73) and the chassis CAN (in variant 1) or chassis CAN 1 (in variant 2) to the Electronic Stability Program control unit.
In model 117.352/952, 156.952, 176.052 up to model year 2016, the DIRECT SELECT INTERFACE transmits the status of the automatic transmission mode button via the drive train CAN and the chassis CAN with the ME-SFI control unit interface to the Electronic Stability Program control unit.
In model 117.352/952, 156.952, 176.052 as of model year 2016, the transmission mode rotary switch transmits a signal via the AMG DRIVE UNIT LIN (LIN B11), the transmission mode control unit (N145) and chassis CAN 1 to the Electronic Stability Program control unit.
The Electronic Stability Program control unit puts the information for the selected transmission mode on the chassis CAN (in variant 1) or on chassis CAN 1 (in variant 2). The control units relevant for the new transmission mode receive the information and switch to the stored parameters for the particular transmission mode.
The CDI control unit or the ME-SFI control unit transmits the signals "Engine speed", "Accelerator pedal position", "Drive train operational" and "Engine running" via the drive train CAN to the all-wheel drive control unit and to the dual clutch transmission fully integrated transmission control unit.
The request "Differential lock" is received by the all-wheel drive control unit via the drive train CAN from the CDI control unit or the ME-SFI control unit.
From the dual clutch transmission fully integrated transmission control unit, the all-wheel drive control unit receives the request "4MATIC control" and the status of the transmission control via the drive train CAN.
The faults are stored in the fault memory. These can be read out using Xentry Diagnostics. The diagnosis status of the all-wheel drive is received by the diagnostic connector (X11/4) from the all-wheel drive control unit via the drive train CAN, the CDI control unit or the ME-SFI control unit, the chassis CAN (in variant 1) or chassis CAN 1 (in variant 2), the electronic ignition lock control unit and the diagnostic CAN (CAN D). Fault messages are shown in the multifunction display (A1p13) in the instrument cluster (A1). In variant 1, the request "Display message" is transmitted by the all-wheel drive control unit via the drive train CAN, the CDI control unit or the ME-SFI control unit and the chassis CAN. In variant 2, the request "Display message" is transmitted by the all-wheel drive control unit via the drive train CAN, the CDI control unit or the ME-SFI control unit, chassis CAN 1, the electronic ignition lock control unit and chassis CAN 2 (CAN E2).
Electrical function schematic for 4MATIC control | Model 117, 156, 176, 246 with transmission 724.0 as of model year 2016 with code M005 (4MATIC) except code 218 (Rear view camera) except code 234 (Blind Spot Monitoring) except code 459 (Steel suspension with adjustable damping) except code 476 (Lane keeping assist) except code 513 (Speed Limit Assist) except code 614 (Bi-xenon headlamps) except code 615 (Bi-xenon headlamps with active light function) except code 618 (Bi-xenon headlamps) except code 621 (Intelligent Light System (left-hand traffic)) except code 622 (Intelligent Light System) except code 631 (Static LED headlamps, left-hand traffic) except code 632 (Headlamps, LED, static, right-side traffic)Model 117, 156, 176, 246 with transmission 724.0 up to model year 2016 with code M005 (4MATIC) | ||
Electrical function schematic for 4MATIC control | Model 117, 156, 176, 246 with transmission 724.0 as of model year 2016 with code 218 (Rear view camera) with code 234 (Blind Spot Monitoring) with code 459 (Steel suspension with adjustable damping) with code 476 (Lane keeping assist) with code 513 (Speed Limit Assist) with code 614 (Bi-xenon headlamps) with code 615 (Bi-xenon headlamps with active light function) with code 618 (Bi-xenon headlamps) with code 621 (Intelligent Light System (left-hand traffic)) with code 622 (Intelligent Light System) with code 631 (Static LED headlamps, left-hand traffic) with code 632 (Headlamps, LED, static, right-side traffic) with code M005 (4MATIC) | ||
Overview of system components, automatically controlled all-wheel drive (4MATIC) |
Referenced documents
- gf2800p9998sva Overview of system components, automatically controlled all-wheel drive (4MATIC)