Mercedes C-Class 722.9 Transmission Control Unit (VGS) / Conductor Plate Repair

The Mercedes C-Class 7G-Tronic (722.9) gearbox control module—also known as the VGS or conductor plate—is a frequent cause of gear shifting issues and limp mode faults. When this module fails, drivers often experience harsh or delayed gear changes, no gear selection, or the gearbox getting stuck in one gear.

During diagnostics, a range of fault codes may be stored in the transmission system, commonly including:

• P0721 – Output Speed Sensor (Y3/8n3) signal faulty or out of range

• P0717 – Turbine Speed Sensor (Y3/8n1) signal not available

• P0722 – Output Speed Sensor (Y3/8n3) signal missing

• P2767 – Internal Speed Sensor (Y3/8n2) signal not available

These codes indicate internal faults within the VGS unit, which monitors gearbox input, output, and internal speed sensors to ensure smooth gear selection.

⚠️ Important Shipping Notice:
If you are sending your Mercedes 7G-Tronic gearbox control unit to VCUS for testing or repair, please remove and send only the plastic electronic module. Do not send the metal valve body or valve chest assembly, as doing so may cause damage to the module during transit.