Reduce Consumers, Basic Function - GF54.10-P-1011A
Model all (CAR)
Overview
This document contains the following information:
- General
- Consumer reduction
General
Switching off or shutting down various functions relieves the load on the 12 V on-board electrical system, if the required electrical power can no longer be supplied. This serves to avoid any significantly negative charge balance for the on-board electrical system battery while also guaranteeing vehicle mobility.
Consumer reduction
When the on-board electrical system voltage drops to a specific value (fleece battery) or when the maximum discharge current is reached (lithium ion battery), the consumer reduction is activated. The first consumer's power consumption level is reduced at the earliest 20 s after the system start. If the cutback conditions remain unchanged, the power consumption of one further consumer will be reduced every following second.
Vehicles with PRE-SAFE® system
PRE-SAFE® measures have a high energy requirement. Therefore when they are triggered, several high-performance consumers are quickly reduced or shut down for the duration of the measures.
Vehicles with 48 V technology, hybrid vehicles or electric vehicles
The energy requirement is provided by the transfer of energy from the 48 V or high-voltage on-board electrical system. If the charge level of the 48 V on-board electrical system battery or the high-voltage battery drops below a defined limit value, energy is no longer transferred.
Various functions are derated or switched off depending on the vehicle equipment involved.
Case A
After the system start, the consumer reduction is activated for a maximum of 10 minutes or as long as the vehicle speed is less than 30 km/h.
| Sequence | Function with power reduction or one that can be switched off |
|---|---|
| 1 | PTC heater booster, stage 6 |
| 2 | PTC heater booster, stage 5 |
| 3 | PTC heater booster, stage 4 |
| 4 | PTC heater booster, stage 3 |
| 5 | PTC heater booster, stage 2 |
| 6 | PTC heater booster, stage 1 |
| 7 | Seat heater stage 3 |
| 8 | Seat heater stage 2 |
| 9 | Steering wheel heater |
| 10 | Rear blower 50 % |
| 11 | Front blower 50 % |
| 12 | Engine fan 50 % |
| 13 | Trunk socket, cigarette lighter |
| 14 | Mirror heater |
| 15 | Spray nozzle hose heater |
| 16 | Wiper park heater |
| 17 | Rear window heater |
| 18 | Windshield heater 50 % |
| 19 | Windshield heater 0 % |
| 20 | Seat heater stage 1, seat ventilation |
| 21 | Residual heat utilization, blower in rear passenger compartment 0 % |
| 22 | Stationary heater, taxi roof sign |
| 23 | Telematics/audio/telephone/GPS |
Case B
- At the latest 10 minutes after system start
- Vehicle speed above 30 km/h
- Before system start, circuit 15R ON
- Energy conversion switched off (combustion engine switched off) or energy transfer configured (vehicles with 48 V technology, hybrid vehicles or electric vehicles) and circuit 15 ON
| Sequence | Function with power reduction or one that can be switched off |
|---|---|
| 1 | PTC heater booster, stage 6 |
| 2 | PTC heater booster, stage 5 |
| 3 | PTC heater booster, stage 4 |
| 4 | PTC heater booster, stage 3 |
| 5 | PTC heater booster, stage 2 |
| 6 | PTC heater booster, stage 1 |
| 7 | Windshield heater 50 % |
| 8 | Wiper park heater |
| 9 | Spray nozzle hose heater |
| 10 | Mirror heater |
| 11 | Seat heater stage 3 |
| 12 | Rear window heater |
| 13 | Steering wheel heater |
| 14 | Seat heater stage 2 |
| 15 | Rear blower 50 % |
| 16 | Front blower 50 % |
| 17 | Engine fan 50 % |
| 18 | Trunk socket, cigarette lighter |
| 19 | Windshield heater 0 % |
| 20 | Seat heater stage 1, seat ventilation |
| 21 | Residual heat utilization, blower in rear passenger compartment 0 % |
| 22 | Stationary heater, taxi roof sign |
| 23 | Telematics/audio/telephone/GPS |
If the on-board electrical system voltage has stabilized to a defined value (fleece battery) or if the permissible discharge current (lithium ion battery) has been undershot, consumer reduction is then canceled. The switched-off consumers or functions are switched-on again in the reverse order with a waiting time in each case of 1 s.
With circuit 15R OFF, and depending on the charge level of the on-board electrical system battery, various consumers (e.g. telematics, stationary heater, standing light) are switched off, but not in a specific sequence.
| Function schematics | |||
| Consumer reduction, function schematic | Model 118, 177, 247 | PE54.10-P-2501-97A | |
| Model 167, 293 | PE54.10-P-2501-97B | ||
| Control units | |||
| Central controller unit, basic function | Model 118, 177, 247 | GF54.21-P-9895A | |
| Front central controller unit basic function | Model 167 Model 293 |
GF54.21-P-9896A |