P2767 on Mercedes-Benz: How to Diagnose & Fix
Input/Turbine Speed Sensor "B" Circuit No Signal
2 Mercedes-Benz models · 2 documented issues · 2 critical · $500-$2,200 repair
P2767 on Mercedes-Benz by model: symptoms, diagnosis and fix
The electronic conductor plate integrated into the 722.9 7-speed automatic's valve body (which houses the internal TCM, speed sensors and shift solenoids) is a widely reported failure on R171 SLKs equipped with the 7G-Tronic. As the plate's internal speed sensors and soldered joints degrade with heat cycling, the transmission drops into limp mode, typically locking into a single forward gear (often 2nd). The condition is temperature-sensitive and commonly appears from roughly 50,000-90,000 miles.
Common Symptoms
- Transmission stuck in gear (often 2nd), won't shift up
- Limp mode / reduced speed limited to ~40 mph
- Harsh or delayed shifts, especially when cold
- Intermittent faults that come and go with temperature
- Speed-sensor fault codes
How to Fix
Replace or rebuild the conductor plate (the revised design), refresh the valve body, and perform a transmission fluid and filter service plus an adaptation reset. Independent specialists offer a cheaper conductor-plate reman as an alternative to Mercedes' full valve-body replacement (roughly $2,000-$3,000 at a dealer). A neglected fluid service accelerates the failure, so periodic 722.9 fluid changes are recommended.
Sources for this issue (3)
The 722.9 7G-Tronic automatic transmission used in later R171 models is known for conductor plate and internal speed sensor failures. When the plate or sensors fail, the transmission may enter limp mode, shift harshly, or get stuck in one gear due to loss of accurate input/output speed data.
Common Symptoms
- Transmission stuck in limp mode
- Harsh or delayed shifting
- Vehicle starts in second gear
- Transmission warning message
- Check engine light or transmission fault codes
How to Fix
Diagnosis involves scanning the transmission control module for speed sensor and gear ratio faults, then confirming fluid condition and connector integrity. Repair usually includes replacing the conductor plate, transmission connector sleeve, fluid, and filter, followed by adaptation reset and relearn. Typical repair cost is about $900-$2,000 at an independent Mercedes specialist.
What you need to fix it
Only diagnosis- and fitment-reviewed repair parts are linked here.
- Genuine Mercedes 722.9 conductor-plate service kit 000270260080OEMMercedes-Benz A000270260080 / kit 000270260080KT
Matched 722.9 VGS/conductor-plate repair after EHS generation and internal speed-sensor failure are confirmed Fitment/availability: The inspected direct U.S.
As an Amazon Associate, we earn from qualifying purchases; other part links may also earn au7o a commission. Confirm fitment by VIN before buying.
Owner tips & cautions
- TipUse the correct Mercedes-spec transmission fluid and perform adaptation reset after repair.
P2767 code reference
General diagnostic-code context. The code alone does not confirm a cause for your vehicle; use the applicable issue card and its sources.
Frequently asked questions
What does P2767 mean on a Mercedes-Benz?
P2767 stands for "Input/Turbine Speed Sensor "B" Circuit No Signal." This code is set when the transmission control module receives no signal from the input/turbine speed sensor "B". This sensor measures how fast the transmission input shaft is turning, which the computer uses to time gear shifts correctly. With no signal, the transmission cannot accurately control shifting and often defaults to limp mode, causing harsh, delayed, or failed shifts. It usually indicates a sensor or wiring fault and should be addressed to restore normal transmission operation. On Mercedes-Benz it is documented across 2 models: SLK/SLC, SLK-Class.
What are the most common causes of P2767?
The most common causes of P2767 are: Faulty input/turbine speed sensor B, Open or shorted sensor wiring, Corroded or loose connector, Damaged reluctor/tone ring, Low or contaminated transmission fluid, Internal valve body or transmission fault, Faulty TCM. The specific cause varies by vehicle.
How much does it cost to fix P2767 on a Mercedes-Benz?
Published repair estimates on Mercedes-Benz range from $500 to $2,200 depending on the model and root cause. If an issue mentions a recall or campaign, check your VIN with the manufacturer or NHTSA and confirm eligibility and coverage with a dealer.
Looking for P2767 on a different make?
View P2767 across all makes →Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.