Unlock SD Connect C4 by PCB Modification

“If your Mercedes-Benz Star diagnosis SD Connect c4 is locked, do not need to buy a new set and just change this chip is ok.” said a Mercedes owner with MB SD C4 diagnostic tool.

Here is the customer solution to unlock MB Star diagnostic tool sdconnect c4 mux.

NOTE: AT RISK TO TRY!

PCB modification procedure:

1- Carefully open the sd connect multiplexer

2- Check whether some part is easy broken

MB SD Connect C4 printed circuit board in a good condition should be:

2016-sd-connect-compact-4-pcb-1

2016-sd-connect-compact-4-pcb-2 2016-sd-connect-compact-4-pcb-3 2016-sd-connect-compact-4-pcb-4 2016-sd-connect-compact-4-pcb-5

 

3- Possible occasion:

Maybe batteries leaked and damaged the PCB.
4- Blow the chip marked with a red circle by a electric hair drier

2016-sd-connect-compact-4-pcb-6

5- Disassemble the chip

6- Write the program to a new chip

7- Install the new chip to the PCB, then assemble PCBs into SD connect c4 mux

8- Start SD c4 mux

9- Connect MB SD C4 multiplexer to the laptop

10- SOLVED! And work like a charm, as a good SD Connect C4 at obd2tool.

If method above cannot help you out please contact OBD2TOOL customer service.

Hope this helps!