P0715 Code: Honda Accord (2018-2023) - Causes, Symptoms & Fixes

No recalls found in NHTSA database

According to the data provided, there are no official NHTSA recalls or owner complaints recorded for the 2018–2023 Honda Accord specifically tied to code P0715. This means the diagnostic guide below uses general knowledge about P0715 and Honda transmission behavior, but data-driven failure frequencies or official Honda-tsb guidance for this exact model/year aren’t present in the supplied data. Use this as a comprehensive starting point, and always confirm with OEM service information if you have access to it.

1. CODE MEANING AND SEVERITY

• What P0715 means: P0715 stands for Input/Turbine Speed Sensor Circuit Malfunction. In most applications, this points to a fault in the transmission input speed sensor circuit (or its signal path) which helps the Powertrain Control Module (PCM) and Transmission Control Module (TCM) determine engine speed relative to the transmission input shaft. On many modern Hondas (including Accord with the 10-speed automatic), this sensor is used for shift scheduling, torque converter operation, and speedometer data.
• Severity: Moderate to potentially severe. A confirmed P0715 can cause harsh or erratic shifting, unexpected upshifts/downshifts, limp-mode behavior, failure to go into gear, and/or incorrect vehicle speed readings. If the fault is persistent or occurs with other related transmission codes, driving should be limited to a safe, cautious path and the issue should be repaired promptly to avoid transmission damage or drivability loss.

2. COMMON CAUSES ON HONDA ACCORD

• Faulty or damaged transmission input speed sensor (ISS) or its electrical connector/wiring harness (corrosion, broken wires, loose pins, moisture).
• Faulty Transmission Control Module (TCM) or its interface with the ISS circuit (including poor ground or power supply).
• Damaged or dirty reluctor ring on the transmission input shaft or misalignment/ foreign material on the sensor face.
• Wiring harness damage near the transmission connector (pinched insulation, abrasion, or shorts to ground/voltage).
• Sensor reference voltage or ground instability (voltage drop due to battery/alternator issues or poor grounds).
• Contaminated or degraded transmission fluid level/quality (though fluid doesn’t feed the ISS directly, overall transmission health can affect signal integrity and shifting behavior).
• Previous repairs or aftermarket wiring that altered the ISS circuit.
• Intermittent electrical fault (cooler/harness movement, thermal expansion).

3. SYMPTOMS

• Check Engine or Transmission warning lights illuminated (P0715 stored in the PCM/TCM).
• Irregular shifting: harsh, delayed, slipping, or incorrect gear engagement.
• Transmission may enter a limp/neutral mode or stay in a single gear.
• Vehicle speedometer reading erratic or inaccurate.
• Cruise control may disengage or show inconsistent behavior.
• Sometimes symptoms are intermittent, appearing only under temperature, load, or RPM changes.

4. DIAGNOSTIC STEPS
   Note: If you lack the tools or experience for any step, consider professional diagnosis. The steps below are a practical, progressive approach.

• Step 0: Verify codes and data

  • Use an OBD-II scanner capable of live data and, if possible, a Honda-compatible OEM or advanced test tool.
  • Confirm P0715 is present and note freeze-frame data (engine RPM, vehicle speed, trans temperature, PID values at the time of fault).
  • Check for any related transmission codes (P0700 baseline transmission control code, P0710, P0716, P0740-like codes, etc.). Note any U-codes (network/communication) that might affect the TCM/ECU.

• Step 1: Visual inspection of ISS circuit and connector

  • Locate the transmission input speed sensor and its connector (consult service manual for exact location on your Accord year/model).
  • Inspect the sensor, its wiring harness, and the connector for signs of damage, corrosion, bent pins, moisture intrusion, or loose connections.
  • If feasible, unplug the connector and inspect the pins; check for bent/pitted pins and clean with appropriate electrical contact cleaner. Reinstall with connector fully seated and latch engaged.
  • Look for signs of water ingress or exposure to heat.

• Step 2: Electrical tests of the ISS circuit (if you are comfortable with electrical work)

  • With the battery disconnected, inspect for continuity between the ISS harness wires and the vehicle harness (refer to the wiring diagram in the service manual). Look for shorts to ground or to the 5V reference line.
  • Check the 5V reference and ground to the ISS sensor using a multimeter (if the vehicle’s service information provides the test procedure and expected values). A consistent 5V supply with a stable ground is required for proper sensor operation.
  • If you have access to a scan tool showing real-time sensor data, monitor the ISS output signal while manually rotating the transmission input shaft (or rotating the engine, depending on how the sensor is driven in your transmission). The ISS should produce a clean, repeating signal corresponding to gear teeth passing the sensor.

• Step 3: Physical sensor/housing condition

  • Inspect the ISS mounting surface for corrosion, burrs, or debris that could affect sensor spacing and signal integrity.
  • Check the reluctor ring (the toothed gear on the input shaft) for damage or missing teeth. Debris or misalignment can distort the sensor signal.

• Step 4: Transmission fluid health and level

  • Check the transmission fluid level with the car on a level surface and at the correct temperature (per owner’s manual). Use the correct dipstick method for your transmission (some Honda automatics have sealed units with no dipstick; service bulletin guidance or workshop manual may apply).
  • Inspect fluid color, smell, and clarity. Very burnt, dark, or metallic fluid can indicate internal issues that could affect transmission operation and signals indirectly.
  • If the fluid is dirty or degraded, perform the appropriate service (drain/fill, possible filter/valve-body service per Honda procedure).

• Step 5: Inspect wiring and grounding

  • Inspect grounds related to the transmission and ECU/TCM. A poor ground can cause erratic sensor readings.
  • Ensure the connector seals are intact and that the wiring isn’t being chafed or pinched in the tight transmission area.

• Step 6: Check for software/updates

  • Check if there are manufacturer service bulletins (TSBs) or firmware updates for the TCM/ECU related to speed sensor input. For the Accord, some reliability updates have been issued in various model-year ranges; confirm via official Honda service information if accessible.

• Step 7: If electrical tests pass, consider mechanical causes

  • If the ISS and wiring test good but the fault persistently returns, there may be a deeper mechanical issue (e.g., sensor reluctor misalignment or internal transmission fault) that requires more in-depth inspection by a transmission technician.
  • A professional diagnosis might include scavenging the transmission’s valve body, sensor alignment tests, or a more thorough inspection of the input shaft area.

• Step 8: Road test and recheck

  • After any repair or sensor replacement, clear codes and test drive to confirm whether P0715 reoccurs. If it returns, pay attention to when (temperature, load, rpm, gear) and note any additional codes.

5. RELATED CODES

• Transmission speed sensor family codes and general transmission fault codes may appear in conjunction with P0715. Commonly observed related codes include:
  • P0700 (Transmission Control System Malfunction) – a generic umbrella code often indicating that other transmission codes are present.
  • P0710, P0711, P0712, P0716 (Sales points and range/performance variants of input/turbine speed sensor circuits), though exact code availability can vary by model year and software.
  • P0740 or related torque converter clutch circuit codes may appear if shifting or torque converter operation is affected.
• Note: Exact related codes can vary by vehicle configuration and software; use your scan tool to check for any other active or stored codes and review live data for symptoms correlation.

6. REPAIR OPTIONS AND COSTS (2025 PRICES)
   Prices vary by region, dealer vs independent shop, and whether you use OEM parts or aftermarket equivalents. The ranges below are typical ballpark figures you might expect in many markets. Always get a written estimate before work.

• Transmission input speed sensor replacement (ISS)

  • Parts: typically $25–$60
  • Labor: roughly $80–$180
  • Estimated total: $105–$240
  • Notes: If the sensor is genuinely failing or the connector is damaged, replacement is straightforward. Accessing the sensor location can be the main labor factor.

• Wiring harness/connector repair or replacement (ISS circuit)

  • Parts: $20–$100 (connector kit or harness piece)
  • Labor: $60–$200 (depends on accessibility and whether harness repair requires removing components)
  • Estimated total: $80–$300

• Transmission fluid service (drain/refill, if recommended)

  • Parts: $10–$50 (new fluid)
  • Labor: $60–$150
  • Estimated total: $70–$200
  • Notes: Some Honda transmissions have serviced fluid intervals; if the fluid is degraded, a proper service can improve overall transmission behavior.

• Valve body service, sensor alignment, or related internal transmission work

  • Parts: $100–$500
  • Labor: $200–$800
  • Estimated total: $300–$1,300
  • Notes: This step is more involved and typically pursued if there are persistent shifting or sensor-related issues after simpler fixes.

• Transmission replacement (if the issue is deemed unsalvageable or if multiple components fail and reliability is a priority)

  • Parts: $1,500–$4,000 (reconditioned or remanufactured transmission; OEM new is much more)
  • Labor: $1,500–$3,000
  • Estimated total: $3,000–$7,000
  • Notes: This is a last-resort option for severe, ongoing transmission problems or when multiple failing components are present.

• TCM/ECU reflash or replacement

  • Reflash/labour: often $0–$200 if dealer or service bulletin is in play; replacement can range $800–$2,000 for parts + labor
  • Notes: Some updates improve fault handling or ISS interpretation; always check for the latest Honda service bulletins.

7. DIY VS PROFESSIONAL

• DIY viable tasks (if you’re comfortable with automotive electrical work):
  • Visual inspection of ISS sensor and connector; cleaning and reseating connectors.
  • Basic wiring inspection for obvious damage, corrosion, or pin issues.
  • Observing live data with a scanner to verify ISS signal behavior.
  • Checking fluid level and basic transmission maintenance (fluid change, if within your manual’s guidelines).
• DIY limitations:
  • Accessing the ISS on a modern Honda may require lifting the vehicle and removing components, which can be risky if you’re not equipped.
  • Electrical diagnostics often require a multimeter with proper specs and, ideally, OEM service documentation.
  • If the issue is mechanical (reluctor ring damage, internal transmission fault) or if fault persists after basic tests, professional diagnosis and possible transmission service are recommended.
• When to seek professional help:
  • The car is in limp mode or cannot reliably move.
  • The fault recurs after basic cleaning and reseating of connectors.
  • You don’t have the tools to test sensor signals or you’re uncomfortable working around the transmission.
  • There are several related codes, intermittent symptoms, or you suspect a deeper transmission problem.

8. PREVENTION

• Regular maintenance and inspection
  • Maintain proper transmission fluid level and use the manufacturer-recommended fluid (Dexron VI or equivalent as specified by Honda for the model year).
  • Replace or service transmission fluid per Honda’s maintenance schedule; use OEM or high-quality equivalents.
• Electrical cleanliness and protection
  • Periodically inspect transmission area for signs of moisture, corrosion, or damaged wiring around the ISS connector.
  • Use dielectric grease when reconnecting electrical connectors to protect against moisture and corrosion (as appropriate per service guidelines).
• Avoid aggressive driving and heat stress
  • Harsh shifting, aggressive acceleration, and heavy towing can increase wear on the transmission and its sensor systems.
  • Allow the engine and transmission to reach normal operating temperatures before demanding heavy loads.
• Updates and recalls (data limitation note)
  • Since no recalls were found in the provided data for this specific make/model/year, there are no active recalls to address in this context. However, always check with a dealer for the latest service bulletins or TSBs that may apply to your vehicle’s VIN. Data limitations mean there could be unpublished or region-specific notices not captured here.
• Preemptive checks
  • If you notice low or erratic sensor readings, it’s smart to monitor live data and address small issues (loose connections, damaged wires) before they evolve into a persistent fault.

Important data limitations

• The provided data shows no owner complaints and no recalls in NHTSA for 2018–2023 Honda Accord related to P0715, which limits the ability to quote real-world failure frequencies or Honda-specific TSBs in this exact model/year. The guide above relies on general OBD-II knowledge, typical transmission ISS behavior, and common repair practices for this class of fault. If you have access to Honda service information or updated TSBs for your exact VIN, prioritize those steps.

If you want, I can tailor the guide further to your exact Accord trim (2.0T vs 1.5T, 10-speed automatic vs other configurations) or help you prepare a checklist to bring to a mechanic with specific questions.