Cockpit Simulator CDU Cannot Control FS2020 PMDG 737-900

Hello, I purchased the Cockpit Simulator CDU with MCP to pair with my FS2020 and PMDG 737-900.

Recently I had an issue where the CS CDU could not control the PMDG 737-900 CDU ( it was normal before )

Operation The FS2020 PMDG 737-900 CDU can be immediately synchronized with the Cockpit Simulator CDU

FS2020 PMDG 737-900 → CS CDU ( OK )
CS CDU → FS2020 PMDG 737-900 ( Not Work )

I have tried updating to latest Cockpit Simulator Bridge v2023.1.7 version, but the problem is still unresolved. (The CDU Firmware version is also the latest version).

Please help me how to solve this problem.

Thank you so much for your help !

Best Regards,


Hello Edward,

Could you please conduct two tests, one is to see if the CDU works properly in MSFS PMDG 737-6/7/800? Another is that does CDU function properly during device test in the bridge software?

Looking forward to your feedback.

Thank you very much and wish you a happy new year!


Hi Support,

Appreciate for your quick response.

Based on your two test suggestions, I can’t test the first one because I only have the PMDG 737-900 module purchased separately.

In the second item, I can use the CS Bridge software to test all functions of the CDU, and everything is successful.

Does this have to do with updating FS2020 patches ?

Thank you so much and happy new year !

Best Regards,

Taiwan Flight Fans

Hi Support,

This problem has been solved.

Because the CS CDU/MCP has been in Idel condition for a long time ( Plug-in Power USB Hub ), the problem was solved after I powered off and restarted it.

However, I found that the CDU buttons have a slight response delay, but they function normally.

Thank you so much for your help.

Best Regards,


Hi Edward,

It’s a good news that the problem has been solved.

For cases of slight delay, try connecting the CDU directly to the computer without going through the Hub to see if there is still buttons response delay in MSFS?

Best Regards