P0715 on 2015-2016 Ford Edge: Input/Turbine Speed Sensor 'A' Circuit Causes and Fixes

What's Unique About the 2015-2016 Ford Edge

The 2015-2016 Ford Edge uses the 6F series automatic transmission (either the 6F35 or 6F55 depending on the engine). While generally reliable, these transmissions can be susceptible to issues with their external sensors and wiring over time. Unlike some transmissions where the sensor is internal, on the 6F35, the TSS is typically an externally mounted sensor, making replacement less labor-intensive as the transmission does not need to be fully disassembled. However, a proper diagnosis is still critical to differentiate between a sensor failure, wiring issue, or a more severe internal transmission problem.

Symptoms You May Notice

• Check Engine Light is on
• Harsh, erratic, or delayed gear shifts
• Vehicle enters "fail-safe" or "limp mode"
• Transmission may be stuck in one gear
• Decreased fuel economy
• Inability to shift gears at all
• Flashing O/D (Overdrive) light on the shifter
🎬 Watch: 4 signs of a bad transmission speed sensor

Most Likely Causes

1. Faulty Input/Turbine Speed Sensor (TSS) 🔴 High Probability → Shop Automatic Transmission Input Shaft Speed Sensor The sensor is an electronic component that is subjected to heat and vibration and can fail over time. Debris or metal shavings in the transmission fluid can also accumulate on the magnetic tip of the sensor, disrupting its signal.
   How to confirm: A technician can use a scan tool to monitor the live data from the TSS. If the reading is erratic, zero, or does not change with engine RPM, the sensor is likely faulty. The sensor's internal resistance can also be tested with a multimeter and compared to the manufacturer's specifications.
   Typical fix: Replace the Input/Turbine Speed Sensor. On the 6F35 transmission, this sensor is located on the outside of the transmission case, making it accessible for replacement without major disassembly. 🎬 Watch: Ford Edge turbine speed sensor replacement walkthrough
   Est. part cost: $30-$80
2. Damaged Wiring or Electrical Connector 🟡 Medium Probability The wiring harness leading to the transmission can be exposed to heat, vibration, and road debris, potentially causing wires to break, chafe, or corrode over time.
   How to confirm: Visually inspect the wiring harness and connector for any signs of damage, corrosion, or loose connections. A multimeter can be used to check for continuity, proper voltage, and ground at the connector.
   Typical fix: Repair the damaged section of the wiring harness or replace the connector pigtail.
   Est. part cost: $20-$50
3. Low or Dirty Transmission Fluid ⚪ Low Probability → Shop Transmission Assembly Neglected maintenance can lead to fluid breakdown and contamination. Metal shavings and other debris in the fluid can interfere with the magnetic operation of the speed sensor.
   How to confirm: Check the transmission fluid level and condition. The fluid should be at the correct level and appear clean (typically red). If it is dark, burnt-smelling, or contains debris, it needs to be changed.
   Typical fix: Perform a transmission fluid and filter change. This may resolve the issue if it's caused by contaminated fluid or restricted hydraulic passages.
   Est. part cost: $100-$250 (for fluid and filter)

Rare But Worth Checking

• Faulty Powertrain Control Module (PCM) or Transmission Control Module (TCM): → Shop Transmission Assembly This is a very uncommon cause. All other possibilities, especially the sensor and wiring, should be exhaustively ruled out before considering module replacement.
• Internal Transmission Mechanical Failure: → Shop Transmission Assembly A more serious internal issue, such as a damaged reluctor ring, failing torque converter, or worn internal components, can also trigger this code. This is usually accompanied by other symptoms like noise or severe slipping.

Diagnosis Steps

1. Connect an OBD-II scanner to read the code and check for any other related codes.
2. Check the level and condition of the automatic transmission fluid. Top off or change if necessary.
3. Perform a thorough visual inspection of the transmission wiring harness and the main connector for any signs of damage, corrosion, or loose pins.
4. Use a scan tool with live data capability to monitor the Input Speed Sensor (TSS) PID. Observe if the RPM reading is present, stable, and corresponds to engine speed.
5. If the signal is absent or erratic, test the sensor's circuit. Check for proper voltage, ground, and signal at the sensor connector using a multimeter and a vehicle-specific wiring diagram.
6. If the wiring is confirmed to be good, test the sensor itself. Check its internal resistance with a multimeter and compare it to the OEM specification (typically 500–1,200 Ω).
7. If the sensor tests faulty, replace the Input/Turbine Speed Sensor.
8. If the problem persists after replacing the sensor and verifying the wiring, further diagnosis of the PCM or internal transmission components may be required by a professional.

Parts You'll Likely Need

• Transmission Input/Turbine Speed Sensor (TSS) (OEM #DL8Z-7M101-A) — This sensor is the most common failure point for the P0715 code. It is an electronic component that wears out over time.
  Trusted brands: Motorcraft, Standard Motor Products (SMP), NTK
  OEM price range: $50-$90
  Aftermarket price range: $25-$60

Related Codes That Often Appear With This One

• P0717 — P0717 indicates 'Input/Turbine Speed Sensor 'A' Circuit No Signal'. A failing sensor or broken wire can cause an erratic signal (P0715) or a complete loss of signal (P0717), so they often appear together.
• P0720 — This code relates to the Output Speed Sensor (OSS) circuit. Sometimes, a wiring issue or module fault affecting the TSS can also impact the OSS circuit, causing both codes to appear.

Technical Service Bulletins (TSBs) & Recalls

• TSB 07-21-11: While for an older 2007-2008 model, this TSB addresses DTC P0715 on the 6F50 transmission, indicating a history of potential intermittent shorts in the TSS sensor.

Platform-Specific Known Issues

• Owner Experience with P0715 and P0717: On the Ford Edge Forum, a user with a 2008 model (which uses a similar 6F50 transmission) reported getting both P0715 and P0717 codes along with a wrench light, even after replacing both the TSS and OSS sensors. This highlights that the issue can sometimes be intermittent or related to the wiring harness or PCM, not just the sensor itself.
• DIY Repair Discussion: A thread on the Ford Truck Enthusiasts forum for a similar transmission details the symptoms of a failing TSS, including banging into gear and a flashing O/D light. The user successfully replaced the sensor, confirming it as the fix. This provides context that a sensor replacement is a common and effective solution for these symptoms.

Diagnostic Flowchart

Other Known Issues on This Vehicle

Issues unrelated to this code that are worth knowing about as an owner of this generation:

• 2.0L EcoBoost Coolant Intrusion 🔴 High — A known issue for 2015-2018 models where a design flaw may allow coolant to leak into the engine's cylinders, potentially causing misfires and engine failure. (Ref: TSB 19-2346)
• Brake Hose Rupture 🔴 High — Affects 2015-2018 models. The front brake jounce hoses can rupture, leading to a brake fluid leak and increased stopping distances. (Ref: Recall 20S42)
• Torque Converter Failure 🟠 Medium — Some owners have reported issues with the torque converter, which can cause shuddering, slipping, and eventual transmission failure. Recalls were issued for bad welds on some model years. (Ref: Recalls in 2017 and 2018)
• Faulty Brake Booster 🟠 Medium — A prevalent issue reported for models up to 2015, where the brake booster may fail, resulting in a hard brake pedal and increased effort to stop the vehicle.
• Door Ajar Warning Light Stays On 🟡 Low — A common complaint where a faulty door latch sensor causes the 'door ajar' warning to remain illuminated, which can drain the battery.

Real Owner Stories

Aggregated from forums and TSBs cited above. Mileages and costs reflect what owners reported in those sources.

Related OBD-II Codes

• P0717 — Often appears alongside P0715 as a companion code indicating a lack of signal from the Turbine Speed Sensor circuit.
• P0720 — Relates to the Output Speed Sensor (OSS); both TSS and OSS sensors are frequently diagnosed together when transmission shift issues occur.
• P0300 — While not a transmission code, engine misfires related to the 2.0L EcoBoost coolant intrusion (TSB 19-2346) can sometimes be confused with transmission shuddering.

Frequently Asked Questions