Transmission Code P0705: Meaning, Symptoms, and How to Fix It

If your car won’t start, shifts harshly, or gets stuck in a limited speed mode, it may be showing the P0705 code. This error affects the Transmission Range Sensor (TRS) and, while it’s not always severe, ignoring it can leave you stranded or lead to more expensive repairs later on.

Today on the Sun Transmissions blog, we’ve prepared a clear guide to what the P0705 code means: its causes, symptoms, how mechanics diagnose it, and the solutions available to fix it.

What Is Transmission Code P0705?

The P0705 code is triggered when the Transmission Range Sensor (TRS) fails to send the correct signal to the vehicle’s computer (ECM/TCM). This sensor tells the system what gear the shift lever is in (Park, Neutral, Drive, Reverse).

When it fails, the computer becomes “confused” and doesn’t know which gear the car is in. This can prevent the engine from starting, cause erratic shifting, or activate limp mode.

In Which Cars Is the P0705 Code More Common?

Although it can appear in many automatic vehicles, this code is more commonly found in models such as:

• Toyota Camry
• Honda Accord
• Nissan Altima
• Ford Focus
• Chevrolet Malibu
• Hyundai Elantra
• Kia Optima

This doesn’t mean it’s exclusive to these brands—it just shows a higher tendency for these models to experience TRS-related failures.

What Causes the P0705 Code?

The causes of this code are mechanical or electrical in nature. Understanding them helps identify what to check first:

• Damaged TRS sensor. Over time and constant use, the internal contacts of the transmission range sensor wear down or get contaminated with debris. This prevents the sensor from sending accurate signals to the computer, leaving it unable to detect the shift lever’s position.
• Faulty wiring. Heat, humidity, and engine vibration deteriorate the wires that connect the TRS to the ECU or TCM. A broken, corroded, or shorted wire disrupts the electrical signal, leading to erratic readings or total signal loss.
• Loose or dirty connectors. Often the issue is not the sensor itself but the connectors. Dust, grease, or corrosion on the terminals can prevent proper contact, causing intermittent failures.
• Low or contaminated transmission fluid. Transmission fluid is essential: it lubricates, cools, and provides hydraulic pressure for shifting. If the fluid level is low or it appears very dark and smells burnt, it has lost its properties. This affects transmission operation and can cause abnormal readings from the sensor.
• ECM or TCM failure. Less common, but an internal fault in the Engine Control Module (ECM) or Transmission Control Module (TCM) can prevent the TRS signal from being read correctly. This usually requires advanced diagnostics and, in some cases, module replacement.
• Shift linkage. This is a frequent and easy-to-mistake cause. The linkage connects the cabin shift lever to the transmission. If misaligned, it can mimic a faulty TRS even when the sensor itself is fine.

What Are the Symptoms of the P0705 Code?

If you notice these signs while driving, it’s important to see a mechanic as soon as possible:

• Difficulty or inability to start the engine.
• Check Engine light illuminated on the dashboard.
• The gear indicator on the dashboard doesn’t match the actual gear.
• Harsh shifting, jerks, or clunks while driving.
• Transmission locked in a single gear.
• Vehicle stuck in limp mode, limited to a maximum speed of 40 mph (64 km/h).

How Is the P0705 Code Diagnosed in a Shop?

To confirm this issue, professional mechanics typically follow these steps:

• OBD-II scan. A scanner is connected to confirm the code and check for related errors.
• Voltage and ground test. A multimeter is used to verify the sensor receives power and has proper grounding.
• Signal check during gear shifts. As the lever is moved, the sensor should output different voltages for each position.
• Resistance test. Reference voltage is measured; if it doesn’t change, the sensor may be faulty.
• Wiring diagram review. Each gear’s output is compared to the manufacturer’s specifications.

Common Mistakes When Diagnosing the P0705 Code

Many shops make mistakes that extend repair times or increase costs:

• Replacing the sensor without first checking the wiring. Sometimes the problem lies in a damaged or loose wire. If the TRS is replaced without inspecting the wiring, the error returns and the customer pays twice.
• Not checking the ATF. Contaminated transmission fluid alters hydraulic pressure and performance. Without inspecting it, mechanics may wrongly blame the sensor.
• Skipping the shift linkage adjustment. A misaligned linkage can mimic TRS failure. If not corrected first, costly parts may be replaced unnecessarily.
• Relying only on the scanner without manual testing. The scanner shows the code, but not always the exact cause. Without voltage, resistance, and continuity checks, the diagnosis can be incomplete or inaccurate.

Is Code P0705 Serious? What You Need to Know

The P0705 code doesn’t always indicate an immediate critical failure, but it can compromise driving and transmission health. Erratic shifting or sudden jerks increase the risk of losing control, while in other cases the car may not start at all or stay stuck in low speed, making it inconvenient and unsafe to drive.

Additionally, a car with the Check Engine light on will not pass emissions or safety inspections, which can become a long-term problem. If not addressed promptly, the transmission can suffer irregular internal wear, reducing its lifespan and leading to much higher repair costs or even full replacement.

How to Fix Transmission Code P0705?

Repairs depend on the root cause, but the most common solutions include:

• Repairing or replacing damaged wiring and connectors.
• Adjusting the shift linkage.
• Changing contaminated transmission fluid and filter.
• Replacing the TRS if confirmed faulty.
• Replacing the ECM or TCM only in severe, verified cases.

Approximate Repair Costs

Prices vary depending on the vehicle model and availability of parts

• New TRS sensor: between $80 and $200 USD.
• Transmission fluid and filter change: starting at $70 USD.
  
• Specialized labor: between $50 and $150 USD, depending on sensor access and shop rates.

Don’t Ignore the Warning: The Importance of Acting Early

The P0705 code may look like just a light on the dashboard, but it’s a clear sign your vehicle needs attention. Ignoring it can escalate into bigger problems—from leaving you stranded to causing serious transmission damage. Timely inspection not only protects your vehicle but also saves money and ensures you drive safely.

Looking for Automatic Transmission Parts?

Don’t let a faulty transmission sensor ruin your trip. At Sun Transmissions, we offer high-quality parts to solve this issue at the root. From TRS sensors to connectors and solenoids, we have everything you need to get your car safely back on the road.

Check out our selection of automatic transmission solenoids and connectors today and avoid more costly repairs tomorrow.