MB SD Connect C4/C5 Star Diagnosis tool cannot measure the car

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MB SD Connect C4/C5 Star Diagnosis tool cannot measure the car

The customer connected the Mercedes-Benz to be tested, opened the MB SD Connect C4/C5 xentry software, and selected the corresponding model. The final step of the test is as follows:

The above problem occurred and the hardware of MB SD Connect C4/C5 was not found. Generally there are three problems:
1. MB SD Connect C4/C5 host problem
2. MB SD Connect C4/C5 network cable problem
3. Computer problem with MB SD Connect C4/C5

The customer connects to the host and computer of the MB SD Connect C5/C4 via a network cable. The host’s MB SD Connect C4/C5 host screen is displayed as follows:

From the display prompt: Device not in use
As you can see, MB SD Connect C4/C5 does not work.
Look at the icon in the red circle: This display is the MB SD Connect C4/C5 host is not connected to the computer.



If the MB SD Connect C4/C5 host is connected to the computer, the icon should look like this:

That may be because
1, network cable problem
2, the network card is broken
3, the network card driver has a problem

Solution:Replace a new network cable (common with ordinary network cable)

1. If you replace the new network cable and the connection is normal as shown below, the original network cable is damaged.

2. If you change the network cable or the following is displayed: that is, the computer’s network card or network card driver has a problem.

3. If it is a driver problem, reinstall the NIC driver to solve it.

4. If the NIC driver is reinstalled, the problem remains the same. That is the problem with the network card, please check or replace the new network card to solve.

At the same time, if your MB SD Connect C4/C5 hardware can be connected to the car, the lower right corner of your computer will display as follows:

If the MB SD Connect C4/C5 hardware is not connected to the car and computer, or if the hardware is not found after the connection, it will be displayed as follows:

If you still have problem to use MB SD Connect C4/C5 Star Diagnostic tool, please contact our sales. <sales@obd2tool.com>

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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.


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-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


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!