Drivetrain control unit, component description - GF54.21-P-2141MNA
ENGINE 177.9 in MODEL 205
View of model 205
Location of front passenger footwell
The powertrain control unit is located in the front passenger footwell and it is fastened to the engine compartment's partition wall.
Task
The powertrain control unit acts as an interface (gateway) between the ME-SFI [ME] control unit and the CAN network, and it fulfills the following tasks:
- Reading in of signals
- Output of signals and actuation of components
Apart from this, the powertrain control unit acts as an interface between the connected CAN bus systems.
Reading in of signals
Input factors are read in by means of the following connections:
- Direct line
- Drive-train-LIN (LIN C3)
- Engine CAN (CAN C)
- Drive train CAN (CAN C1)
- User interface CAN (CAN HMI)
- Chassis FlexRay (Flex E)
Output of signals and actuation of components
Initial parameter are output over the following connections:
- Direct line
- Drive train LIN
- Engine CAN
- Drive train CAN
- User interface CAN
- Chassis FlexRay
The input factors that have been read in are evaluated by the integrated microprocessor and the affected components are then actuated.
The electronic ignition lock control unit (N73) is the central interface (gateway) for exchanging the function-relevant data of the control units that are connected to the various CAN bus systems.
Input factors and output factors for the following components are read in or output over direct lines by the powertrain control unit:
| Input factors over a direct line | Initial parameters over a direct line | Supplemental information |
|---|---|---|
| Terminal 15 | - | - |
| Terminal 30 | - | - |
| Circuit 30 (fused) | - | - |
| Circuit 31 | - | - |
| Terminal 87 | - | - |
Input factors and output factors for the following components and control units are sent or received by the powertrain control unit over LIN or CAN:
| Input factors over engine CAN (CAN C) | Output factors via engine CAN (CAN C) | Supplemental information |
|---|---|---|
| ME-SFI control unit (N3/10) | ME-SFI control unit (N3/10) | - |
| Input factors via drive train CAN (CAN C1) | Output factors via drive train CAN (CAN C1) | Supplemental information |
|---|---|---|
| ME-SFI control unit (N3/10) | ME-SFI control unit (N3/10) | - |
| AMG suspension control unit (N3/43) | AMG suspension control unit (N3/43) | With CODE 466 (Active engine mount) or CODE 467 (AMG rear axle electronic locking differential) |
| Fuel system control unit (N118) | Fuel system control unit (N118) | - |
| Fully integrated transmission control unit (Y3/8n4) | Fully integrated transmission control unit (Y3/8n4) | - |
| Input factors over user interface CAN (CAN HMI) | Initial parameters over user interface CAN (CAN HMI) | Supplemental information |
|---|---|---|
| Electronic ignition lock control unit (N73) | Electronic ignition lock control unit (N73) | - |
| Input factors over chassis FlexRay (Flex E) | Output factors over chassis FlexRay (Flex E) | Supplemental information |
|---|---|---|
| Instrument cluster (A1) | Instrument cluster (A1) | Over the user interface CAN (CAN HMI) and electronic ignition lock control unit (N73) |
| Head unit (A26/17) | Head unit (A26/17) | Over the user interface CAN (CAN HMI) and electronic ignition lock control unit (N73) |
| Audio/COMAND control panel (A40/9) | Audio/COMAND control panel (A40/9) | Over the telematics CAN (CAN A), head unit (A26/17), user interface CAN (CAN HMI) and the electronic ignition lock control unit (N73) |
| Supplemental restraint system control unit (N2/10) | Supplemental restraint system control unit (N2/10) | Over the user interface CAN (CAN HMI) and electronic ignition lock control unit (N73) |
| Front SAM control unit (N10/6) | - | via interior CAN (CAN B) and electronic ignition lock control unit (N73) |
| Climate control unit (N22/1) | Climate control unit (N22/1) | via interior CAN (CAN B) and electronic ignition lock control unit (N73) |
| Electronic Stability Program control unit (N30/4) | Electronic Stability Program control unit (N30/4) | - |
| Adaptive damping system control unit (N51/5) | Adaptive damping system control unit (N51/5) | With CODE 488 (AMG RIDE CONTROL sports suspension) or with CODE 492 (AMG performance suspension) |
| Radar sensors control unit (N62/1) | Radar sensors control unit (N62/1) | With CODE 23P (Driving Assistance package) |
| Left front door control unit (N69/1) | - | via interior CAN (CAN B) and electronic ignition lock control unit (N73) |
| Electronic ignition lock control unit (N73) | Electronic ignition lock control unit (N73) | - |
| Steering column tube module control unit (N80) | - | - |
| Input factors over drive-train-LIN (LIN C3) | Output factors over drive-train-LIN (LIN C3) | Supplemental information |
|---|---|---|
| Fan motor (M4/7) | Fan motor (M4/7) | - |
| Low-temperature circuit circulation pump 1 (M43/6) | Low-temperature circuit circulation pump 1 (M43/6) | - |
| Low temperature circuit circulation pump 2 (M43/7) | Low temperature circuit circulation pump 2 (M43/7) | - |
Body
The powertrain control unit housing is made of plastic. The dust-proof powertrain control unit is installed in the vehicle interior.
Ground connection
The "circuit 31" ground connection is made via multiple ground lines to the left and right front footwell ground point (W15/5 and W15/7).
Voltage supply
The powertrain control unit is powered by "circuit 30 directly", by "circuit 30 fused" and also with ignition ON by "circuit 87". In the control voltage range, it has both short-circuit protection and reversed polarity protection. Power is supplied through several parallel-connected pins in order to relieve the electrical connections.
Computer power-down
Information for partial function "no-load current shutoff" is documented in the function description "Engine OFF energy management function".
Variants
The control unit variants, e.g. national, exhaust and function variants, are activated by Xentry Diagnostics using the variant coding function.
| Wiring diagram for powertrain control unit | N127 | PE54.21-P-2141-97FBA |