Shows model 246 |
N112/9 | HERMES control unit |
P82.89-2398-06
Location
The HERMES control unit is installed in the trunk behind the left side wall trim, except in model 117.9. On model 117.9, the HERMES control unit is secured behind the rear seats at the major assembly carrier on the right side.
Tasks
The HERMES control unit is responsible for the following tasks:
Prioritization of the services in the internal arithmetic unit
Self-diagnosis, secures operational readiness of emergency call system by checking the following facts:
Receipt of cyclic readiness signal ("Sign of life") from the supplemental restraint system control unit (N2/10)
Connection for muting audio sources (mute function)
Connection to hands-free system microphone (B25/12), via the audio equipment
Connection to following antennas:
Emergency call system antenna (A2/52) (model 117.3, 176, 242 or model 117.9, 156, 246 up to 31.05.2018)
Emergency call system antenna 1 (A2/140) (model 117.9, 156, 246 as of 01.06.2018)
Antenna of emergency call system 2 (A2/141) (model 117.9, 156, 246 with code 362 (HERMES LTE) and with code 379 (Telephone module with Bluetooth® (SAP profile)), code 386 (Convenience Telephony), code B24 (Remote control for stationary heater) as of 01.06.2018; model 156, 176 with code 360 (HERMES UMTS) and with code 379 (Telephone module with Bluetooth® (SAP profile)), code 386 (Convenience Telephony), code B24 (Remote control for stationary heater))
Multifunction antenna (model 242, 246 with code 362 (HERMES LTE) and with code 536 (SIRIUS satellite radio), model 117.3)
Antenna for telephone and stationary heater (model 117.9, 156 with code 362 (HERMES LTE) and except code 379 (Telephone module with Bluetooth® (SAP profile)), except code 386 (Convenience Telephony), except code B24 (Remote control for stationary heater), model 242, 246 with code 362 (HERMES LTE) and except code 536 (SIRIUS satellite radio), except code 379 (Telephone module with Bluetooth® (SAP profile)), except code 386 (Convenience Telephony), except code B24 (Remote control for stationary heater); model 156, 176 with code 360 (HERMES UMTS) and except code 379 (Telephone module with Bluetooth® (SAP profile)), except code 386 (Convenience Telephony), except code B24 (Remote control for stationary heater))
Reception of crash signals from the supplemental restraint system control unit as trigger signal for the automatic emergency call (input)
Build-up of voice or data links to service provider over emergency call system antenna, emergency call system antenna 1, emergency call system antenna 2, multifunction antenna or telephone and stationary heater antenna (input and output)
For voice connections: Transmission of a muting signal (mute function) to the sound system amplifier control unit (N40/3) (with code 810 (Sound system)) or to the audio equipment (except code 810 (Sound system)) (output)
For voice connections: Reception of signals from the hands-free system microphone by the audio equipment (input)
For voice connections: Transmission of audio signals to the center instrument panel speaker (H4/27)
Power supply over circuit 30 and circuit 31 (input)
Reception of GPS signals (Global Navigation System) for position finding (with code 505 (Radio 20 NTG5 not navigation compatible), with code 520 (Audio 20 USB)), over the multifunction antenna (model 117.3) or over the GPS antenna (A2/23) (except model 117.3) (input)
Real-time traffic data communication with audio equipment over a USB connection (Universal Serial Bus) (with code 367 (Live Traffic Information)), for vehicles with code 357 (Map navigation) over USB splitter (A2/128) (input and output)
Communication of Internet signals over Bluetooth® interface and Bluetooth® antenna to radio (A2) (with code 522 (Audio 20 radio) and code 494 (USA version)) (Bluetooth® interface)
Communication of Internet signals through a wireless connection over the WLAN antenna (A2/83) to COMAND controller unit (A40/3) (with code 531 (COMAND APS) und with code 494 (USA version)) (radio interface)
In model 242.890 (Electric vehicle): CAN communication over the hybrid CAN (CAN L) to the powertrain control unit (N127) (CAN interface)
CAN communication over diagnostic CAN (CAN D) with electronic ignition lock control unit (N73) (CAN interface)
The HERMES control unit can, e.g. receive the following CAN signals over the diagnostics CAN from the electronic ignition lock control unit:
Circuit 15 status as trigger signal for self-diagnosis of emergency call system
Cyclic readiness signal ("sign of life") from the supplemental restraint system control unit as check signal
Crash information from the Supplemental Restraint System control unit (redundant), including crash level
Position data from audio equipment (with code 522 (Audio 20 radio) or with code 531 (COMAND APS))
Control signals from emergency call system button (S93/3s2) (manual emergency call)
Operation signals from breakdown assistance button (S93/3s4) and MB-Info button (S93/3s5) (with code 494 (USA version))
Control signals of the button groups on the multifunction steering wheel from the instrument cluster (A1) (e.g. volume control, muting, establish or disconnect connection)
Signals of the steering wheel angle sensor (N49) from the steering column tube module control unit (N80), for position finding (with code 505 (Radio 20 NTG5 non-navigation capable), with code 520 (Audio 20 USB))
Wheel speed signals, yaw rate signals from the Electronic Stability Program control unit (N30/4) for position finding (with code 505 (Radio 20 NTG5 non-navigation capable), with code 520 (Audio 20 USB))
In model 242.890 (Electric vehicle), the HERMES control unit can, e.g. receive the following CAN signals over the hybrid CAN from the powertrain control unit:
Vehicle data on the charge level, for expected charging period and range
Vehicle data for pre-entry climate control
The HERMES control unit can, e.g. send the following signals over the diagnostics CAN:
Map data and miscellaneous data sent from the service center ("Remote Information Feed") via the electronic ignition lock control unit to the audio equipment
Status and test signals to emergency call system button (manual emergency call)
Status and test signals to breakdown assistance button and to MB-Info button (with code 494 (USA version))
Status signals via the electronic ignition lock control unit to the instrument cluster
Display messages to display on Audio/COMAND display (A40/8)
Operating requests
In model 242.890 (Electric vehicle) the HERMES control unit sends, e.g. remote data requests and control signals over the hybrid CAN to the powertrain control unit.
"HERMES" stands for: "Hardware for Enhanced Remote, Mobility & Emergency Services".
The HERMES control unit is prepared to send and receive for a period of 30 days. As soon as an SMS is received, the HERMES control unit is also activated (wake-up); after 30 days the emergency call system goes into sleep mode.
Structure
Internet-capable communications module
Bluetooth® interface
Radio interface for wireless local area network (WLAN)
Position finding module
GPS receiver for position finding (date, time, history and last-known location) for the listed vehicle-related services
Memory for vehicle-specific data
Buffer for navigation and other data that is transmitted to the vehicle