The steering wheel paddle shifters in your 2019 Mercedes-Benz C-Class provide sporty manual gear control without removing hands from the wheel. When these paddles stop working, the connection between switch input and transmission control needs diagnosis.
Paddle Shifter System
The paddle shifters are switches that send signals through the clock spring to the transmission control module. When activated in manual mode, they command upshifts or downshifts. The system requires proper shift mode selection and functional electrical path.
Mode Requirements
Verify the transmission is in the correct mode for paddle operation. Sport mode or manual mode typically activates paddle function. In normal drive mode, paddles may not respond or have limited function. Check current mode selection.
Clock Spring Function
The clock spring (spiral cable) carries signals from the paddle switches to the vehicle wiring. Clock spring failures affect paddle function along with other steering wheel controls. If multiple wheel functions fail, the clock spring is suspect.
Switch Failures
Individual paddle switches can fail mechanically or electrically. If one paddle works and the other doesn't, that specific switch has likely failed. Both paddles failing simultaneously suggests shared circuit issues rather than both switches failing.
Transmission Module Communication
Paddle signals must reach the transmission control module. Communication faults or module issues can prevent paddle commands from being executed even when switches and wiring work correctly.
Code P0705 Context
Code P0705 relates to transmission range sensor or gear selection issues. While not directly a paddle code, transmission-related faults may affect or accompany paddle function issues.