P0722 on Mercedes-Benz
Output Speed Sensor Circuit No Signal
P0722 on Mercedes-Benz vehicles indicates output speed sensor circuit no signal. Au7o has documented this code across 2 Mercedes-Benz models — most commonly on C-Class, E-Class. This code means the transmission control module is receiving no signal at all from the output speed sensor, which measures how fast the transmission's output shaft (and therefore the vehicle) is turning. The computer relies on this sensor to time gear shifts, control the torque converter, and confirm road speed, so when the signal drops out it suspects a broken circuit or dead sensor. You may notice harsh or erratic shifting, the transmission staying in one gear, or an inaccurate or dead speedometer. It is an electrical/no-signal fault rather than just an out-of-range reading. Typical repair costs on Mercedes-Benz range from $500 to $3,000, depending on the specific model and root cause.
Common Causes of P0722
- •Failed output (vehicle) speed sensor
- •Broken, corroded, or loose sensor wiring or connector
- •Open or shorted circuit between sensor and TCM
- •Damaged sensor reluctor/tone ring on the output shaft
- •Metal debris or contamination on the sensor tip
- •Poor ground or power supply to the sensor
- •Faulty transmission control module (less common)
P0722 on Mercedes-Benz by Model
Mercedes-Benz C-Class(1 issue)
- 7G-Tronic Valve Body Failure2005-2013
The 722.9 7G-Tronic automatic transmission develops valve body issues causing harsh or delayed shifts, particularly the 2-3 and 4-5 upshifts. The conductor plate (electrical connector inside the valve body) is also failure-prone.
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.
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View P0722 across all makes →Frequently Asked Questions
What does P0722 mean on Mercedes-Benz?▼
P0722 stands for "Output Speed Sensor Circuit No Signal." This code means the transmission control module is receiving no signal at all from the output speed sensor, which measures how fast the transmission's output shaft (and therefore the vehicle) is turning. The computer relies on this sensor to time gear shifts, control the torque converter, and confirm road speed, so when the signal drops out it suspects a broken circuit or dead sensor. You may notice harsh or erratic shifting, the transmission staying in one gear, or an inaccurate or dead speedometer. It is an electrical/no-signal fault rather than just an out-of-range reading. On Mercedes-Benz specifically, this code is documented across 2 models.
What causes P0722 on Mercedes-Benz vehicles?▼
Common causes on Mercedes-Benz: Failed output (vehicle) speed sensor, Broken, corroded, or loose sensor wiring or connector, Open or shorted circuit between sensor and TCM, Damaged sensor reluctor/tone ring on the output shaft, Metal debris or contamination on the sensor tip. Specific causes vary by model and year — see the per-model sections below.
How much does it cost to fix P0722 on a Mercedes-Benz?▼
Repair costs on Mercedes-Benz range from $500 to $3,000, depending on the specific model and root cause.
Which Mercedes-Benz models have P0722 documented?▼
Au7o has documented P0722 on 2 Mercedes-Benz models: C-Class, E-Class.