This is one of the most frequent OBD2 trouble codes. Read the full article below to know what it means, how to fix it, and what other codes may show related to it.
Definition
P0722 is an OBD-II Code that refers to Output Speed Sensor No Signal
Meaning
A P0722 code is a generic diagnostic trouble code that occurs when the PCM/ECM receives a signal indicating the transmission system’s output speed sensor is not sending sufficient information.
The transmission's output speed sensor will not produce a coherent or expected speed signal when the PCM cannot detect one. As a result, it will be unable to correctly anticipate how and/or when to shift up or down. When this happens and the P0722 code is set and stored in the memory.
Causes
Common causes for this code include:
- Bad Output Speed Sensor
- Fluid that is dirty or contaminated
- The transmission filter may be dirty or blocked.
- Coolant is dirty or contaminated or incorrect
- Malfunctioning Temperature Sensor
- The Transmission Valve Body hydraulic passages might be restricted
- Faulty Shift Solenoid Corroded or damaged connector may be faulty
- Damaged wiring
- Bad PCM
Symptoms
The symptoms of a P0722 code are:
- Illuminated Check Engine Light
- Reduced fuel economy
- Transmission does not shift
- Bad shifting that is erratic
- Vehicle enters limp mode
- Incorrect or erratic speedometer reading
Diagnosis
To diagnose a P0722 DTC code, a technician would:
- Scan for codes in the ECM and look at the freeze frame data for failure.
- Visually inspect the output speed sensor and all related wiring for damage, rubbing, etc.
- Check the transmission fluid level and condition.
- Check the operation of the shifter to ensure it is in the correct position.
- Test the power and ground circuits to the output speed sensor with a multimeter.
- Check the reference voltage at the output speed sensor connector.
Common mistakes
The following are some of the most common mistakes that a technician may make when diagnosing a P0722 code:
- Not thoroughly inspecting all the wiring and connectors.
- Not checking the fluid level and condition.
- Not testing the power and ground circuits.
- Not checking the reference voltage at the output speed sensor connector.
How serious is this?
A P0722 code is a serious code, as it can prevent the transmission from shifting correctly and may cause damage.
What repairs can fix the code?
The following are solutions that may fix this problem:
- Repairing or replacing a faulty transmission output speed sensor
- Repairing or changing a faulty or broken engine coolant temperature sensor
- Replacing a damaged or faulty shift solenoid
- Flushing the system and replacing the transmission fluid
- Replacing a failed valve body
- Testing and troubleshooting the output speed sensor's circuit.
Related codes
A P0722 is related to and may be accompanied by the following codes:
P0700: Transmission Control System (MIL Request)
P0702: Transmission Range Sensor Circuit Low Input
P0703: Transmission Range Sensor Circuit High Input
P0704: Clutch pedal Position Switch Circuit Fault
U0401: Invalid Data Received from PCM/ECM
Conclusion
In conclusion, the P0722 code is a diagnostic trouble code that refers to a problem with the output speed sensor not sending a signal. This code is a serious code that can cause damage to the transmission if not fixed. The most common cause for this code is a faulty output speed sensor, but it can also be caused by other issues such as a faulty shift solenoid or a damaged wiring harness. If you have this code, it is important to have it diagnosed and repaired as soon as possible.