Drivetrain control unit, component description - GF54.21-P-2141MRH
MODEL 205.047/147/247 with ENGINE 274.9
Shown: Model 205.0
Location
The powertrain control unit is secured in the vehicle interior to the inner partition wall to the engine compartment.
Tasks
The powertrain control unit acts as an interface between the ME-SFI [ME] control unit and the CAN network, and it fulfills the following tasks:
- Regulation of engine cooling
- Reading in of signals
- Evaluation of input factors
- Output of signals and actuation of components
Apart from this, the powertrain control unit acts as an interface (Gateway) between the connected CAN bus systems. The energy management module is integrated into the powertrain control unit and it coordinates the energy flows from the hybrid system and - based on the electrical variables - it forms the interface to the control units for the battery management system (N82/2), power electronics (N129/1) and the electric A/C compressor (A9/5).
Information on energy management is documented in the function description for the "Energy management hybrid system".
Regulation of engine cooling
The powertrain control unit controls the fan motor (M4/7), the radiator trim flap actuator motor (M2/37) with (CODE 5U3 (AIRPANEL)), the electric coolant pump (M75/11) with (CODE 494 USA version)), the low-temperature circuit switchover valve (Y73/1) and low-temperature circuit circulation pump 1 (M43/6) over the drive train LIN (LIN C3).
Reading in of signals
Input factors are read in by means of the following connections:
- Direct line
- Drivetrain LIN
- Engine CAN (CAN C)
- Drive train CAN (CAN C1)
- Chassis FlexRay (Flex E)
- Periphery CAN (CAN PER)
- Hybrid CAN (CAN L)
Evaluation of input factors
The input factors that have been read in are evaluated by the integrated microprocessor and the affected components are then actuated.
Output of signals and actuation of components
Initial parameter are output over the following connections:
- Direct line
- Drivetrain LIN
- Engine CAN
- Drive train CAN
- Chassis FlexRay
- Peripherals CAN
- Hybrid CAN
The electronic ignition lock control unit (N73) is the central interface (Gateway) for exchange of function-relevant data for control units which are connected to the various Control Area Network (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 | - | - |
| Circuit 30 | - | - |
| Circuit 30 (fused) | - | - |
| Circuit 31 | - | - |
| Low temperature circuit temperature sensor (B10/13) | - | - |
| Low-temperature circuit 2 temperature sensor (B10/24) | - | - |
| Evaporator temperature sensor (B10/6) | - | - |
| - | High-voltage battery cooling system expansion valve (Y110) | - |
| - | High-voltage battery cooling system switchover valve (Y140) | - |
| - | Heater booster relay (K16/3) | Cold countries |
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 drivetrain CAN (CAN C1) | Output factors via drivetrain CAN (CAN C1) | Supplemental information |
|---|---|---|
| ME-SFI control unit (N3/10) | ME-SFI control unit (N3/10) | - |
| Fuel system control unit (N118) | Fuel system control unit (N118) | - |
| Fully integrated transmission control unit (Y3/8n4) | Fully integrated transmission control unit (Y3/8n4) | - |
| Accelerator pedal module control unit (B37n1) | Accelerator pedal module control unit (B37n1) | - |
| Input factors over drive-train-LIN (LIN C3) | Output factors over drive-train-LIN (LIN C3) | Supplemental information |
|---|---|---|
| Radiator trim flap actuator (M2/37) | Radiator trim flap actuator (M2/37) | with CODE 5U3 (AIRPANEL) |
| Fan motor (M4/7) | Fan motor (M4/7) | - |
| Low-temperature circuit circulation pump 1 (M43/6) | Low-temperature circuit circulation pump 1 (M43/6) | - |
| Electric coolant pump (M75/11) | Electric coolant pump (M75/11) | With CODE 494 (USA version) |
| Low-temperature circuit switchover valve (Y73/1) | Low-temperature circuit switchover valve (Y73/1) | - |
| Input factors via hybrid CAN (CAN L) | Starting data via hybrid CAN (CAN L) | Supplemental information |
|---|---|---|
| Battery management system control unit (N82/2) | Battery management system control unit (N82/2) | |
| Power electronics control unit (N129/1) | Power electronics control unit (N129/1) |
| Input factors via periphery CAN (CAN PER) | Output factors via periphery CAN (CAN PER) | 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 |
|---|---|---|
| Electronic Stability Program control unit (N30/4) | Electronic Stability Program control unit (N30/4) | - |
| AIRmatic control unit (N51/3) | AIRmatic control unit (N51/3) | With CODE 483 (ADVANCED AGILITY package) and CODE 489 (AIRmatic) |
| Radar sensors control unit (N62/1) | Radar sensors control unit (N62/1) | With code 23P (Driving Assistance package Plus) |
| Electronic ignition lock control unit (N73) | Electronic ignition lock control unit (N73) | - |
| Steering column tube module control unit (N80) | Steering column tube module control unit (N80) | - |
Body
The powertrain control unit housing is made of plastic. The dust-proof powertrain control unit is installed in the vehicle interior.
Ground connection
"Circuit 31" is connected to ground over the right front footwell ground point (W15/7).
Voltage supply
The powertrain control unit is powered directly by "Circuit 30", through a "Fused circuit 30" and with ignition ON by "Circuit 87". In the operating 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.
| Designation | Unit | Values | Tolerance range | Remarks |
|---|---|---|---|---|
| Powertrain control unit (N127) | ||||
| Voltage supply | V | 12 | ||
| Supply voltage | V | 13, 5 | ||
| Voltage limits | V | 6...18 | ||
| Power consumption | A | >1 | Operating current | |
| No-load current | mA | 300 | Circuit 30 no-load current | |
| Reverse polarity protection | Yes | |||
| Low temperature circuit temperature sensor (B10/13) | ||||
| Model | NTC resistor (negative temperature coefficient) | |||
| Resistor | Ω | 235, 36 | at 90°C | |
| 3117, 78 | at 20°C | |||
| 8267, 38 | at 0°C | |||
| Radiator trim flap actuator motor (M2/37) with (CODE 5U3 (AIRPANEL)) | ||||
| Model | Electric actuator motor, actuation via drive train LIN (LIN C3) | |||
| Supply voltage | V | 9 to 16 | Circuit 87 M2 and circuit 30, ground terminal 31 | |
| No-load current | μA | 30 | Max. 50 | |
| Fan motor (M4/7) | ||||
| Model | Electric fan | |||
| Supply voltage | V | 12 | Circuit 87 M2 and circuit 30 | |
| Supply voltage | V | 6...18 | ||
| Specified speed of the fan | Over drive train LIN from ME-SFI [ME] control unit | |||
| No-load current | mA | 0, 3 | ||
| Average operating current | A | 50 | ±2 | |
| Low-temperature circuit circulation pump 1 (M43/6) | ||||
| Model | Electric coolant pump | |||
| Supply voltage | V | 12 | ||
| Supply voltage | V | 8 to 16 | ||
| Rated current | A | ≤ 9 | ||
| Nominal delivery quantity | m3/h | 1, 8 | ||
| Nominal delivery pressure | bar | ≥ 0.75 | ||
| Electric coolant pump (M75/11) with (CODE 494 (USA version) | ||||
| Model | Electric coolant pump | |||
| Supply voltage | V | 12 | ||
| Low-temperature circuit switchover valve (Y73/1) | ||||
| Model | Electrical actuator | |||
| Supply voltage | V | 12 |
| Wiring diagram for powertrain control unit | N127 | PE54.21-P-2141-97FBA |