P0717 on Mercedes-Benz
Input/Turbine Speed Sensor Circuit No Signal
P0717 on Mercedes-Benz vehicles indicates input/turbine speed sensor circuit no signal. Au7o has documented this code across 4 Mercedes-Benz models — most commonly on C-Class, E-Class, M-Class. This transmission code means the computer is receiving no signal from the input/turbine speed sensor, which measures how fast the transmission's input shaft (turbine side of the torque converter) is spinning. The computer compares this against engine and output speeds to control shifts and torque converter lockup. With no signal, it can't manage shifting properly, so you may get harsh or erratic shifts, no torque converter lockup, or limp mode. It is a no-signal electrical fault pointing to the sensor or its circuit. Typical repair costs on Mercedes-Benz range from $300 to $2,200, depending on the specific model and root cause.
Common Causes of P0717
- •Failed input/turbine speed sensor
- •Open or shorted wiring to the sensor
- •Corroded or loose sensor connector
- •Damaged reluctor/tone ring on the input shaft
- •Metal debris on the sensor tip from internal wear
- •Poor ground or reference voltage to the sensor
- •Faulty transmission control module (less common)
P0717 on Mercedes-Benz by Model
Mercedes-Benz C-Class(1 issue)
- 722.6 5G-Tronic conductor plate failure (limp mode, stuck in 2nd gear)1996-2002
The 722.6 five-speed automatic (fitted to W202 facelift cars from ~1996 onward and all 2001-2002 W203s) uses an electronic conductor plate mounted on top of the valve body that integrates the speed sensors and routes signals to the solenoids. The plate fails for two reasons: (1) the internal RPM sensors get coated by ferrous wear particles when the fluid is never changed, producing implausible-slip codes, and (2) the soldered traces and embedded capacitor crack from heat cycling. Failure puts the transmission into limp-home mode — stuck in 2nd gear, harsh 1-2 and 2-3 shifts, or no upshift at all. Often accompanied by codes P0717, P0720, P0731-P0736 and a transmission warning light. This is the single most common 722.6 failure across every Mercedes chassis that uses it.
Mercedes-Benz E-Class(1 issue)
- 7G-Tronic Conductor Plate Failure2003-2012
The 722.9 7G-Tronic transmission conductor plate (internal electrical board with speed sensors) fails, causing limp mode, harsh shifting, and loss of gears. The electrical connector corrodes or the sensors crack from heat cycling.
Mercedes-Benz M-Class(1 issue)
- 722.9 7G-Tronic Conductor Plate (TCM) Failure and Limp Mode2006-2015
The 722.9 7G-Tronic automatic transmission fitted to ML350, ML500/550 and other gasoline M-Class models uses an internal conductor plate that doubles as the transmission control module and houses the input/turbine speed sensors. Heat, ATF breakdown and vibration cause the molded-in speed sensors and the plate's electronics to degrade internally. The transmission then loses the ability to monitor input-shaft speed and torque-converter slip, producing harsh, delayed or 'thumping' shifts that start out intermittent and eventually become permanent. In the worst case the transmission locks into a single gear (typically 2nd) and enters limp mode. This is one of the most widely reported 7G-Tronic faults across the W164/W166 M-Class. Repair is plug-and-play once codes are cleared with a STAR/equivalent scanner.
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 P0717 across all makes →Frequently Asked Questions
What does P0717 mean on Mercedes-Benz?▼
P0717 stands for "Input/Turbine Speed Sensor Circuit No Signal." This transmission code means the computer is receiving no signal from the input/turbine speed sensor, which measures how fast the transmission's input shaft (turbine side of the torque converter) is spinning. The computer compares this against engine and output speeds to control shifts and torque converter lockup. With no signal, it can't manage shifting properly, so you may get harsh or erratic shifts, no torque converter lockup, or limp mode. It is a no-signal electrical fault pointing to the sensor or its circuit. On Mercedes-Benz specifically, this code is documented across 4 models.
What causes P0717 on Mercedes-Benz vehicles?▼
Common causes on Mercedes-Benz: Failed input/turbine speed sensor, Open or shorted wiring to the sensor, Corroded or loose sensor connector, Damaged reluctor/tone ring on the input shaft, Metal debris on the sensor tip from internal wear. Specific causes vary by model and year — see the per-model sections below.
How much does it cost to fix P0717 on a Mercedes-Benz?▼
Repair costs on Mercedes-Benz range from $300 to $2,200, depending on the specific model and root cause.
Which Mercedes-Benz models have P0717 documented?▼
Au7o has documented P0717 on 4 Mercedes-Benz models: C-Class, E-Class, M-Class, SLK/SLC.