Your vehicle is equipped with many sensors to monitor the different components of your engine and transmission. These sensors work along with the powertrain control module (PCM) to ensure the efficient working of the various parts of your vehicle. One of these sensors is known as a transmission input speed sensor or turbine speed sensor. When the transmission input speed sensor goes bad, your PCM triggers the P0715 code. This article mainly explains the P0715 code meaning, symptoms, and causes.
P0715 Code Definition
Diagnostic Trouble Code (DTC) P0715 code stands for “malfunction in the transmission input/turbine speed sensor circuit.”
What Does the P0715 Code Mean?
The trouble code P0715 is related to the communication between a vehicle’s engine and transmission. The P0715 code is triggered when the Powertrain Control Module (PCM) detects wrong voltage signals coming from the transmission input speed sensor.
The input speed sensor is located on or inside your vehicle’s transmission. It measures the rotating speed of the transmission’s input shaft.
Typically, this sensor contains three wires. It is designed to detect the reluctor ring’s motion within the transmission. As your vehicle triggers the P0715 engine code, the vehicle enters into the limp mode. This mode restricts your car’s speed and power to mitigate potential damage to other engine parts.
The TCM or PCM of your vehicle triggers the limp mode because they don’t have correct information about the transmission’s speed, making it unsafe to determine the appropriate gear shift.
P0715 Code Causes
The P0715 code is caused by one or more of the following reasons:
- Bad or damaged input speed sensor
- Damaged reluctor ring
- Faulty or damaged speed sensor wiring
- Bad or damaged output speed sensor
- Damaged speed sensor electrical connection
- Dirt on the input speed sensor
- Bad shift solenoid
- Damaged transmission valve body
- Faulty torque converter
- Contaminated transmission fluid
- Transmission fluid leaks
- Dirt on the output speed sensor
P0715 Code Symptoms
- Check Engine Light illumination
- Poor fuel efficiency
- Your car goes into limp mode
- Erratic speedometer
- Shifting issues
- Abnormal transmission operation
- Stalling when coming to a stop
- Transmission overheating
- Poor engine performance
- No noticeable adverse conditions in some cases
- Vehicle stuck in one gear
How to Diagnose the P0715 Code
You need the following tools to diagnose or fix the P0715 code:
- Vehicle Specific Service Manual
- A suitable diagnostic scanner, a digital volt/ohmmeter (DVOM)
- Basic Hand Tools
- Multimeter
- A system wiring diagram
Follow the below-given steps to diagnose the DTC p0715:
- Visually inspect the input/turbine speed sensor to check its condition and the condition of its wiring.
- Connect the scanner to the diagnostic port and retrieve all stored codes. Make a note of all stored codes for future reference. You should also note freeze frame data, if available.
- If both input sensor and output sensor codes are present, use the scanner data stream to determine which circuit is malfunctioning. Narrow the data stream to include only related data for more responsive data delivery.
- When removing sensors, check for excessive metal debris on magnetic contacts. Remove excessive debris before reinstallation. Inspect interruption grooves and reluctor wheel notches when sensors are removed.
- Test individual sensors using the DVOM and following the manufacturer’s specifications (found in the service manual or through All Data).
- Replace sensors that fail to comply with specs. Disconnect related controllers before testing resistance and continuity with the DVOM. Failure to do so could cause controller damage.
- Test system circuits for shorted or open wiring.
- Repair or replace defective circuits.
- If all system circuits and sensors are in proper working order, suspect a faulty PCM or a PCM programming error.
Common P0715 Code diagnosis mistakes
- Replacing the input speed sensor without inspecting the reluctor ring.
- Replacing the input speed sensor without properly checking for damaged input speed sensor wiring.
- Replacing the input speed sensor without checking the level of the transmission fluid.
- Replacing the unnecessary parts.
What repairs can fix the P0715 Code?
The most common repairs for the P0715 code are as follows:
- Replacing the input/turbine speed sensor
- Replacing the torque converter
- Repairing damaged wiring for the input speed sensor
- Replacing the output speed sensor
- Repairing or replacing the PCM
- Replacing the shift solenoid
- Removing the dirt from the input speed sensor
- If your transmission fluid is contaminated or low, then change the fluid or add more fluid
P0715 Code Repair Cost
For the P0715 code, you may need one or more of the below repairs to fix the original problem. For each possible repair, the estimated cost includes the cost of the relevant parts and the labor required to make the repair.
| Parts | Cost |
|---|---|
| Input speed sensor replacement | $90 to $310 |
| Torque converter replacement | $610 to $1600 |
| Output speed sensor replacement | $90 to $310 |
| Wiring repair/replacement | $90 to $1100 |
| Transmission replacement | $1700 to $4600 |
FAQ Section
Can I drive the car with the P0715 code?
The P0715 code indicates a severe issue. Therefore, it is recommended to stop driving as your PCM triggers this code. This trouble code can put the vehicle into a fail-safe mode that causes harsh gear changes and possibly cause the vehicle not to accelerate at all. The vehicle may not be driveable with this code present.
What is an input speed sensor?
The Input Shaft Speed Sensor measures the rotational speed of the Input Shaft, taken from the upper countershaft drive gear. The Main Shaft Speed Sensor measures the rotational speed of the transmission gearing exiting the main case, taken from the auxiliary upper countershaft gear.
How serious is the P0715 code?
P0715 code can affect a vehicle differently as some will cause no noticeable issues, while others will cause the transmission to simply not shift. An automatic transmission that won’t shift is not only inconvenient, but it’s dangerous as well.
What does the transmission speed sensor do?
The speed sensor detects a gear or target wheel in the transmission and generates an electric digital signal proportional to the speed of rotation. The transmission controls use this information to modify various transmission functions such as shift points and perform diagnostic tests.
Can you drive with a broken input speed sensor?
Generally, driving a vehicle with a broken input speed sensor is unsafe. The car’s computer will not be able to determine the speed that your vehicle is traveling, so it might apply the brakes at a faster rate than necessary or increase the engine power.
What causes a vehicle input speed sensor to malfunction?
Failing to follow your vehicle maintenance schedule can increase the risk of speed sensor failure. The speed sensor will not be able to produce correct readings if the magnetic pickup and/or toothed wheel become heavily covered in gunk, particularly old transmission fluid contaminants.
Is a speed sensor easy to replace?
Yes, replacing a wheel speed sensor is easy and takes you about an hour at maximum. You can also remove the ABS wheel speed sensors separately, keeping other parts integrated into the wheel bearing hub assembly.
How long does it take to replace the transmission sensor?
If you get a professional to do the job, then it should take about 2 to 3 hours to replace the range sensor.