Electric Drive Activation, Basic Function - GF08.00-P-1009A
Electric vehicles
Overview
This document contains information on:
- General
- Function requirements
- Electric drive activation
General
The activation function in the powertrain control unit requests the precharging of the high-voltage intermediate circuit and the switching on of the contactor. It then assesses the status of the contactor and reports that the system is ready by outputting the signal "drivetrain operational".
Function requirements
- Circuit 15 ON
- No crash signal in this ignition cycle
- Active and trouble-free CAN bus connections to all high-voltage components
- High voltage security checked and released (no crash in interlock circuit error, no insulation fault)
- No charging cable plugged in
Electric drive activation
The following conditions must be met in order for the activation function to output the signal "drivetrain operational":
- Drive range P or N is active
- Brake is applied
- Driver requests starting procedure
- High-voltage battery voltage is in permissible range
- High-voltage battery temperature is in permissible range
- Electric machine is operational
- Contactor is closed
When circuit 15 is switched on, the activation function in the powertrain control unit requests the precharging of the capacitors in the high-voltage intermediate circuit. After precharging is complete and the appropriate feedback, it requests that the contactor be switched on.
The battery management system control unit reports in the status signal that the contactor has been switched on. If the status signal fails, the activation function sets the status of the contactor internally to a substitute value.
Following the successful activation of the high-voltage on-board electrical system, the powertrain control unit sets the status of the drivetrain to "operational".
The powertrain control unit transmits this status via the networking so that a corresponding message is displayed to the driver.
| Function schematics | |||
| Function schematic for electric drive activation | Model 243 | PE08.00-P-2504-97A | |
| Model 295, 296, 297 | PE08.00-P-2504-97B | ||
| Additional basic functions | |||
| Power electronics control unit, basic function | GF08.20-P-9891A | ||
| Electric drive powertrain control unit, basic function | GF08.20-P-9892A |