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
P0715 is an OBD-II Code that refers to Input/Turbine Speed Sensor Circuit Malfunction
Meaning
A P0715 code is a generic diagnostic trouble code which refers to the transmission being unable to read the RPM of the engine, keeping it from shifting properly and causing erratic and hard transmission. If the input sensor doesn't get a signal that is within the specified parameters established by the manufacturer, the transmission will not be able to read the engine's RPM, resulting in an Error Code P0715.
Causes
Common causes for this code include:
- Bad Transmission Speed Sensor
- The wiring of the transmission speed sensor has been damaged or is open
- Defective shift solenoids
- Transmission valve body is damaged
- Clogged or dirty transmission fluid
- Transmission fluid is at low levels
Symptoms
The symptoms of a P0715 code are:
- Engine Light ON (or Service Engine Soon Warning Light)
- Transmission shift points that are unpredictable or harsh
- Increased vehicle fuel use
- The transmission doesn't shift.
- The speedometer (odometer) has been fluctuating in speed.
- No speedometer operation
- When the engine comes to a halt, it may stall
Diagnosis
To diagnose a P0715 DTC code, a technician would:
- Scan for codes in the ECM and look at the freeze frame data
- Remove the transmission speed sensor and check it for damage or dirt build-up
- Replace the transmission speed sensor if found to be defective or damaged
- Check wiring, connectors and solenoids which may be damaged
- After all of the above is complete and no error codes remain in memory, road test vehicle and recheck to see if the P0715 code returns
- If it doesn't, the repairs were successful. If it does return after repair, further diagnosis is needed to check for a possible leak in a vacuum hose or another system malfunction
Common mistakes
The following are some of the most common mistakes that a technician may make when diagnosing a P0715 code:
- Not checking the freeze frame data to determine the conditions under which the DTC was set
- Trying to diagnose a transmission problem when only the P0715 code is stored in memory
- Not checking for proper voltage or ground at the connector to the speed sensor
- Not cleaning or replacing the faulty part
- Replacing parts that aren't bad, such as solenoids and sensors which haven't been tested yet.
How serious is this?
A P0715 code is considered to be a medium-priority code. If the condition causing the DTC isn't found and corrected, it could lead to more severe transmission problems such as slipping or a no-start situation.
What repairs can fix the code?
The following are solutions that may fix this problem:
- The input speed sensor is replaced
- Repairing of damaged wiring in the input speed sensor
Related codes
A P0715 is related to and may be accompanied by the following codes:
P0716 – Transmission Speed Sensor Malfunction
U0100 – Lost Communication with ECM/PCM
U0101 – Lost Communication With TCM
P0720 – Output Speed Sensor Malfunction (This is the RPM reading from the output speed sensor)
P0721 – Output Speed Sensor No Signal
Conclusion
In conclusion, the P0715 code is a diagnostic trouble code that refers to a malfunction in the transmission speed sensor. This malfunction can often be resolved by replacing a faulty transmission speed sensor, which is relatively inexpensive and quick to replace.