P2768 on Mercedes-Benz
Input/Turbine Speed Sensor 'B' Circuit Intermittent
P2768 on Mercedes-Benz vehicles indicates input/turbine speed sensor 'b' circuit intermittent. Au7o has documented this code across 1 Mercedes-Benz model — most commonly on SLK/SLC. A generic OBD-II transmission code. The input/turbine speed sensor reports how fast the torque converter turbine and transmission input shaft are spinning, and the transmission control module uses that against output speed to manage shift timing and torque converter lockup. P2768 sets when the module receives an erratic, irrational, or otherwise unusable signal from the sensor designated 'B' — present but dropping out or implausible rather than completely missing. Because the module is getting bad speed data, you may notice harsh or flaring shifts, no torque converter lockup, delayed engagement, or stalling when coming to a stop. Typical repair costs on Mercedes-Benz range from $500 to $2,200, depending on the specific model and root cause.
Common Causes of P2768
- •Failing input/turbine speed sensor 'B'
- •Intermittent wiring fault — chafed harness, broken wire, or damaged shielding on the sensor circuit
- •Corroded, loose, or fluid-contaminated connector at the transmission case pass-through
- •Low or contaminated transmission fluid, or metal debris on the sensor tip
- •Damaged reluctor/tone ring or excessive input shaft endplay giving an erratic signal
- •Failed transmission control module or its internal wiring
P2768 on Mercedes-Benz by Model
Mercedes-Benz SLK/SLC(1 issue)
- 7G-Tronic (722.9) Conductor Plate / Valve Body Failure Causing Limp Mode2005-2011
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.
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View P2768 across all makes →Frequently Asked Questions
What does P2768 mean on Mercedes-Benz?▼
P2768 stands for "Input/Turbine Speed Sensor 'B' Circuit Intermittent." A generic OBD-II transmission code. The input/turbine speed sensor reports how fast the torque converter turbine and transmission input shaft are spinning, and the transmission control module uses that against output speed to manage shift timing and torque converter lockup. P2768 sets when the module receives an erratic, irrational, or otherwise unusable signal from the sensor designated 'B' — present but dropping out or implausible rather than completely missing. Because the module is getting bad speed data, you may notice harsh or flaring shifts, no torque converter lockup, delayed engagement, or stalling when coming to a stop. On Mercedes-Benz specifically, this code is documented across 1 model.
What causes P2768 on Mercedes-Benz vehicles?▼
Common causes on Mercedes-Benz: Failing input/turbine speed sensor 'B', Intermittent wiring fault — chafed harness, broken wire, or damaged shielding on the sensor circuit, Corroded, loose, or fluid-contaminated connector at the transmission case pass-through, Low or contaminated transmission fluid, or metal debris on the sensor tip, Damaged reluctor/tone ring or excessive input shaft endplay giving an erratic signal. Specific causes vary by model and year — see the per-model sections below.
How much does it cost to fix P2768 on a Mercedes-Benz?▼
Repair costs on Mercedes-Benz range from $500 to $2,200, depending on the specific model and root cause.
Which Mercedes-Benz models have P2768 documented?▼
Au7o has documented P2768 on 1 Mercedes-Benz model: SLK/SLC.