Mercedes-Benz Warning Message
“Gearbox Malfunction”
The Mercedes 7G-Tronic or 9G-Tronic transmission has detected a critical fault. The transmission may enter limp mode, locking into 2nd or 3rd gear. This is the highest-value repair lead in the Mercedes ecosystem.
critical severity
Common Causes
- Conductor plate (valve body) failure
- Torque converter lockup clutch wear
- Transmission speed sensor malfunction
- Electrical connector corrosion
- Transmission fluid contamination
Immediate Action
Stop driving immediately if the transmission slips or jerks. Limp mode is a protective measure — do not attempt to override it. Tow to a qualified shop.
Typical Repair Cost
$3,000–$8,000+