Component description for power electronics control unit - GF08.20-P-1001MEH
ENGINE 272.974 in MODEL 221.095/195
Vehicle phantom view
Location
The power electronics control unit (N129/1) is integrated in the power electronics module and located on the right below exhaust manifold. Shielding occurs by means of a heat shield to protect against thermal radiation.
Interlock circuit
The interlock circuit serves to provide contact protection of persons against accidental touching of high-voltage components. A 12 V/88Hz interlock signal is sent for this purpose through all of the removable or openable components of the high-voltage system. To do this there is a contact bridge in each removable high-voltage plug connection which interrupt the interlock circuit during removal of the high-voltage plug connection. The interlock circuit is also led switched in a series over the 12 V control unit plug connection of the high-voltage components.
High-voltage wiring harness
The power electronics module is a component of the electrical wiring harness which contains the high-voltage fuse box (F70) and the associated high voltage lines. Components must be completely replaced in the case of a defect one of the components in the wiring harness.
View of the engine from the front right
Structure of the power electronics module
Task
General
The power electronics control unit actuates the integrated starter alternator (A79) on request by means of a three-phase AC voltage. It monitors the temperature of the integrated starter alternator and makes diagnoses and predictions available regarding the available torque to the ME-SFI [ME] control unit (N3/10)
Coding
The power electronics control unit is flashable which means that the complete software in the control unit can be updated. The software required to program the control units is stored on the STAR DIAGNOSIS DAS Update DVD.
CAN data bus
The power electronics control unit is connected via the drive train sensor CAN (CAN I) to the CAN network of the vehicle and exchanges data with the other control units.
Input and output signals
The power electronics control unit evaluates the following input signals and issues the corresponding output signals:
- Direct input signals
Direct output signals
CAN input signals
CAN output signals
Direct input signals
- Circuit 30c (crash signal from pyrotechnical separating element (K88))
- Circuit 30
- Circuit 31
- Circuit 50
- Circuit 87f
- Engine speed signal (internal combustion engine)
- High voltage 126 V+
- High voltage 126 V -
- Integrated starter alternator (charging current from alternator operation)
- High voltage interlock
- Rotor position sensor (L20)
- Temperature sensor for integrated starter alternator (B94/1)
Direct output signals
- High voltage 126 V+
- High voltage 126 V -
- Integrated starter alternator (actuation for engine operation)
- High voltage interlock
- Power supply for the rotor position sensor (L20)
- Power supply for the integrated starter alternator temperature sensor (B94/1)
CAN input signals
ME-SFI [ME] control unit (N3/10)
- Engine hood closed/open
- Cooling circuit power electronics coolant temperature
- Request for torque prognosis
- Voltage requests and predictions
- Current requests and predictions
- Electrical limits
- Rotational speed/torque specifications
- Request for intermediate circuit discharge
Battery management system control unit (N82/2)
- Voltage values for high-voltage battery (A100g1)
- Energy requirements
Central gateway control unit (N93)
- Request for diagnostic data
EIS [EZS] control unit (N73)
- Circuit 15 ON
CAN output signals
Battery management system control unit (N82/2)
- High voltage interlock
- Voltage and current values of the integrated starter alternator
Central gateway control unit (N93)
- Diagnostic data
ME-SFI [ME] control unit (N3/10)
- Available torque - static/dynamic
- Electrical actual values
- Performance of the integral starter-alternator
- Emergency running
- Status of the intermediate circuit discharge
- Voltage values for high-voltage battery
- Voltage and current values of the integrated starter alternator
| Wiring diagram for the power electronics control unit | N129/1 | PE54.10-P-2106-97SAA |