Connect the negative battery lead of the auxiliary battery in the engine compartment

Removing the vehicle battery cover 

• Lift battery earth lead (1).
• Remove special tool 2 452 007  .

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  Connecting the negative battery cable of the 48-V battery 

  NOTE: RISK OF DAMAGE 
  Damage to 48-V battery 
  If a 48-V battery that is disconnected from the electrical system is activated, the battery electronics will be damaged. 

  • Only carry out activation of the 48V electrical system with a completely connected 48-V battery.
  WARNING: Incorrect screw connection of the battery cable. 
  Risk of fire! 

  • Make sure that the battery cable is screwed together with the correct  nut.

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• Release the negative battery cable (2) of the 48-V battery from the mounting.
• Position the negative battery cable (2) of the 48-V battery on the negative battery terminal.
• Tighten nut (1).
  TIGHTENING TORQUES SPECIFICATION
  
  

  Negative battery cable to 48-V battery
  Nut M8	Tightening torque	19 Nm

• Connect the connector (1) of the CAN bus and lock it.
• Clip in clip (2).

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  Connecting negative battery cable lead of the vehicle electrical system support battery 

  NOTE: Schematic diagram is for example purposes. Some parts may differ in certain details.
• Position the negative battery lead of the vehicle electrical system support battery (2) on the negative battery terminal as shown.
• Tighten nut (1).
  TIGHTENING TORQUES SPECIFICATION
  
  

  Battery earth lead to battery
  Nut M6	Tightening torque	5 Nm

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  Connecting negative battery cable of 12-V dual storage system 

  NOTE: TECHNICAL INFORMATION 
  Follow notes for 12 V dual storage system.
  See additional information 61 20... NOTES  on the 12 V dual storage system.
  NOTE: Schematic diagram is for example purposes. Some parts may differ in certain details.

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• Release negative battery cable of the 12-V-dual storage system (2) from the mount.
• Position the negative battery cable of 12-V dual storage system (2) as shown on the negative battery terminal.

  The nut (1) is connected to the negative battery cable of the dual storage battery (2) in a way that it cannot be lost.

• Tighten nut (1).
  TIGHTENING TORQUES SPECIFICATION
  
  

  Negative battery terminal 12V dual storage system
  Nut	Tightening torque	19 Nm