Repair SD Connect C4 (SDConnect), Star Diagnosis C3.

Repair SDConnect C4, Star Diagnosis C3. Reworking.

We carry out repairs, improvements Mercedes Star Diagnosis C3, C4 (SDConnect).

Faults arising during operation, such as:

  • “The initialization of the diagnostic multiplexer failed …”
  • lack or interruption of communication between the laptop and the multiplexer
  • the multiplexer cannot initialize individual car blocks
  • SDConnect not updating – dcdi_eErrorcode = 204 (204)
  • SDConnect – batteries are not charging (“Insert batteries”, “Check batteries”, “Batteries can not be charged”)
  • Star Diagnosis C3 stopped working after connecting to trucks (24V)


and many other malfunctions need to repair the hardware of the multiplexers.

Multiplexers SDConnect C4 and Mercedes Star Diagnosis C3 are made on multilayer boards that do not protract from overheating, with a high density of elements. Just a simple replacement of elements may not be enough, some microcircuits must be flashed with appropriate dumps before installation. Therefore, independent repair of such equipment is associated with the risk of its final failure without the possibility of recovery.

Also for Mercedes SDConnect multiplexers we perform full comprehensive reworking:

  • Change the serial number (unlock). Update firmware.
  • Instal the Shutdown function (complete power off without additional switches) see video.
  • Resolving the “Insert / Check Batteries” battery charging error “batteries can not be charged”.
  • Replacing the stock (factory) NEC WiFi card with the original D-Link used in the original SDConnect multiplexers.
  • Battery installation.
  • Calibration measurement of car battery voltage (false warning of low battery voltage)
  • We can also replace your C4 housing with a C5 housing. For the C5 case – install a central processor heat sink, cooler and lithium batteries.

For Star Diagnosis C3 multiplexers, we are finalizing it for working with Mercedes vehicles with an on-board voltage of 24V (trucks, buses, etc.).