Component description for DC/DC converter control unit - GF54.10-P-3006MEH

MODEL 221.095/195 with ENGINE 272.974 

Phantom view of right front of vehicle 

Location 

The DC/DC converter control unit (N83/1) is integrated in the DC/DC converter module. The DC/DC converter module is located in the right front wheel well at the rear.

Interlock circuit

The interlock circuit is used for protecting people against accidental contact with high-voltage components. A 12 V/88Hz interlock signal is looped through all removable or high-voltage system components to be opened. To this end, each removable high-voltage plug connection has a contact bridge, which interrupts the interlock circuit when the high-voltage plug connection is removed. In addition to this, the interlock circuit is connected in series through the 12 V control unit plug connections for the high-voltage components.

Design of DC/DC converter module 

Task 

General 

The DC/DC converter control unit is a bidirectional DC voltage converter which produces a high-voltage direct voltage and a 12 V direct voltage. The DC/DC converter module enables energy exchange between the high-voltage on-board electrical system and the 12 V on-board electrical system when it transforms high-voltage direct voltage (primary voltage) into 12 V direct voltage (secondary voltage) and vice versa. As a result an equalization of battery energy between the on-board electrical systems and starting assistance function is made possible at an external voltage of 14 V.

Coding 

The DC/DC converter control unit is flashable i.e. the complete software in the control unit can be updated (replaced). The software required to program the control units is stored on the STAR DIAGNOSIS DAS Update DVD.

CAN data bus 

The DC/DC converter control unit is connected to the CAN interconnection of the vehicle via the drive train sensor CAN (CAN I) and exchanges data with other control units.

Input and output signals 

The DC/DC converter control unit evaluates the following input signals and issues the corresponding output signals:

• Direct input signals 
• Direct output signals 
• CAN input signals 
• CAN output signals 

Direct input signals 

• Terminal 30
• Circuit 30c (CRASH signal from pyrotechnical separator (K88))
• Circuit 30g
• Terminal 31
• Circuit 87f
• High voltage 126 V+
• High voltage 126 V -
• High voltage interlock

Direct output signals 

• Terminal 30
• Terminal 31
• High voltage 126 V+
• High voltage 126 V -
• High voltage interlock

CAN input signals 

ME-SFI [ME] control unit (N3/10) 

• STANDBY MODE
• BOOST MODE
• BUCK MODE

Central gateway control unit (N93) 

• Request for diagnostic data

CAN output signals 

ME-SFI [ME] control unit (N3/10) 

• Input and output current values
• Standby mode, status
• Boost mode, status
• Buck mode, status

Battery management system control unit (N82/2) 

• High voltage interlock

Central gateway control unit (N93) 

• Diagnostic data

Wiring diagram control unit DC/DC converter

N83/1

PE54.10-P-2105-97SAA