Electric Drive System - High-Voltage Battery Software Update
Date: April 18, 2012Order No.: SM-B-54.21/04
Group: 54
SUBJECT: MY-All, Model 451.391 /491
High-Voltage Battery Software Update
WARNING!
Risk of death and personal injury may occur when touching components on vehicles with high-voltage on-board electrical system if not done properly. Do not touch components and open lines of the high-voltage on-board electrical system.
Persons who are carriers of electronic implants (e.g. cardiac pacemakers) should not carry out any work on high-voltage on-board electrical systems due to increased risk of death or personal injury.
Work on a high-voltage system or on hybrid components may only be conducted by certified workshop personnel. NO OTHER WORKSHOP PERSONNEL may perform work on the high voltage system or hybrid components. HV batteries must always be handled in line with AH54.10-P-0006-01MEV.
MBUSA High-Voltage Awareness e-Learning course, TECH717 must be successfully completed before diagnosing a HV vehicle and proceeding with service has even further requirements. Service work that is not HV-related, such as tire replacement, can also be done by professionals meeting the same minimum requirement of high voltage awareness training.
To prevent flash cancellation with accompanying hardware damage, the 12-V supply (low-voltage connector) chargers or smart charger control units (SCCU) must be detached during the flash process. Note that bus load is reduced during the software update.
Procedure
1. Switch off the ignition and ensure the charging cable is plugged in.
2. Unplug low-voltage (12V) connectors on the control unit side from SCCU (Figure 1) (2) and OnBoard chargers (Figure 1) (1).
3. Update the software for the high-voltage battery.
4. After successfully updating, connect the low-voltage (12V) connectors to SCCU (Figure 1) (2) and OnBoard chargers (Figure 1) (1) again.
Chargers:
^ High-voltage charger control unit (N24/3) (smart)
SCCU Control Units:
^ External communications control unit socket (N24/4) (smart)