Nissan Sunny with an automatic transmission is a reliable car, but even it has problems with the electronics over time. One of the most insidious malfunctions is related to automatic transmission selector position sensor (inhibitor switch or range sensor). This small element is responsible for correctly transmitting the signal about the selected mode (P/R/N/D) to the control unit, and its failure can immobilize the car or cause dangerous malfunctions in the transmission.

In this article we will look at how recognize sensor failure based on symptoms and error codes, carry out diagnostics with a multimeter, and also replace it yourself without contacting service. We will place special emphasis on Nissan Sunny with boxes RE4F03A And RE4F04Bwhere this problem occurs most often. If your car suddenly stops responding or catches fire Check Engine with an error P0705 — the material will be especially useful.

What is an automatic transmission selector position sensor and how does it work?

Selector lever position sensor (aka inhibitor switch or range sensor) is an electromechanical device installed on the automatic transmission housing. Its main task is determine the current position of the shift lever (Park, Reverse, Neutral, Drive, etc.) and transmit this information to ECU (electronic control unit) and other vehicle systems.

On Nissan Sunny sensor integrated with start blocking mechanism (neutral safety switch), which does not allow the engine to start if the selector lever is not in the positions P or N. Structurally, the device is:

  • 🔹 Movable rod with a spring connected to the selector lever;
  • 🔹 Contact group (resistive tracks or reed switches);
  • 🔹 Electronic module with a connector for connecting to wiring;
  • 🔹 Housing with fastenings to the gearbox.

When the driver moves the lever, the sensor rod changes position, closing or opening the contacts. ECU reads the change in resistance or signal from the reed switches and “understands” which mode is selected. On Sunny with RE4F03A the sensor outputs analog signal (change in resistance), and on newer models - digital (impulses).

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On some versions Nissan Sunny The selector lever position sensor is combined with automatic transmission oil temperature sensor. When replacing, it is important to choose an analogue with an identical connector and number of contacts!

Signs of a sensor malfunction: when it’s time to sound the alarm

Failure of the selector lever position sensor rarely occurs suddenly - it is usually preceded by characteristic symptoms, which can be noticed in advance. Here are the most common signs of Nissan Sunny:

  • ⚠️ Engine won't start in positions P or N (the starter does not respond to turning the key);
  • ⚠️ Lights up Check Engine with errors P0705, P0706, P0730;
  • ⚠️ Incorrect mode display on the dashboard (for example, the D, although the lever is in R);
  • ⚠️ Jerks or delays when changing gears;
  • ⚠️ Automatic transmission freezes in one mode (for example, does not exit Park).

The symptom is especially dangerous when the car exits mode on its own Park - this may lead to unintentional movement of the car in the parking lot! On Sunny with a mileage of more than 150 thousand km, the sensor often begins to “fail” due to contact wear or oil getting into the housing.

📊 What symptom of a sensor malfunction have you encountered?
  • Engine won't start
  • Check Engine light on
  • Incorrect mode display
  • Jerks when switching
  • Other

Error codes related to the selector position sensor

If the dashboard lights up Check Engine, the first thing you need to do is read the error codes. For Nissan Sunny The most relevant codes indicating problems with the sensor:

Error code Description Probable Cause
P0705 Range Sensor Circuit Malfunction Broken wiring, oxidation of contacts, sensor failure
P0706 Incorrect selector position sensor signal (Range Sensor Circuit Range/Performance) Wear of resistive tracks, moisture or oil ingress
P0730 Incorrect Gear Ratio The sensor transmits incorrect data about the selected mode
P1705 Transmission Range Sensor Circuit Malfunction Problems with the sensor wiring or connector

On Sunny with RE4F04B error P0705 often accompanied engine start failure - the control unit does not “see” that the selector is in P or N, and blocks the starter. In this case, you can temporarily bypass the blocking by closing the contacts 30 And 50 on the sensor connector (but this is risky - only for emergency starting!).

⚠️ Attention: If on your Nissan Sunny errors are flashing at the same time P0705 And P0730, the problem may lie not only in the sensor, but also in automatic transmission control unit or hydraulic system. In this case, a comprehensive diagnosis is required.

How to check the selector lever position sensor with a multimeter

Before replacing the sensor, it must be diagnose. To do this, you will need a multimeter with resistance and voltage measurement mode, as well as connector pinout diagram for your model Sunny. Below are step-by-step instructions:

  1. Remove the connector from the sensor (usually it is located on the automatic transmission housing next to the selector lever).
  2. Check the power circuit:
    • 🔧 Connect the multimeter in mode 20V DC between contacts +12V (usually pin 1) and mass (pin 4).
    • 🔧 When the ignition is on, the voltage should be 11.5–12.5 V.
  • Check resistance between signal contact (pin 2) and mass in different selector positions:
    Position Resistance (Ohm)
    P0–50
    R100–150
    N200–250
    D300–350
  • Check wiring integrity from sensor to ECU (breaks or short circuits).

    • If resistance doesn't change when switching the lever or shows ∞ (break), the sensor is faulty. Also note contact oxidation — they can be cleaned with alcohol or a special spray.

    Check supply voltage (12V)|Measure resistance at each lever position|Inspect connector for oxidation|Check wiring to ECU-->

    Step-by-step replacement of the sensor with Nissan Sunny

    If diagnostics confirm a malfunction, the sensor must be replaced. On Sunny This procedure does not require removing the box, but will require partial dismantling of the central tunnel and care when working with connectors. Here are the detailed instructions:

    1. Preparation:
      • 🔧 Disable negative battery terminal;
      • 🔧 Remove the plastic trim around the selector lever (unscrew the screws or snap off the clips);
      • 🔧 Loosen the clamp and remove selector lever from the sensor.
    2. Removing the old sensor:
      • 🔧 Disconnect the wiring connector;
      • 🔧 Unscrew 2-3 bolts securing the sensor to the automatic transmission housing (usually by 10);
      • 🔧 Carefully remove the sensor without damaging the rod.
    3. Installing a new sensor:
      • 🔧 Check that new sensor rod was in a position P;
      • 🔧 Install the sensor in place and secure with bolts;
      • 🔧 Connect the connector and selector rod;
      • 🔧 Put the tunnel cover back in place.

    Critical: When installing a new sensor on Nissan Sunny with RE4F03A necessary calibrate its position using a diagnostic scanner (for example, Consult-III or Launch X431). Without calibration, automatic transmission malfunctions are possible!

    How to bypass start blocking with a faulty sensor?

    If the sensor fails and you need to drive urgently, you can temporarily close the contacts 30 (starter power supply) and 50 (lock control) on the sensor connector. It's dangerous! — the car can be started in any position of the selector, which is fraught with an accident. Use only for towing to service!

    Sensor selection: original vs analogues

    When purchasing a new sensor for Nissan Sunny important to consider automatic transmission modification and year of manufacture of the car. Original spare parts from Nissan have articles:

    • 🔧 32510-31X00 - for Sunny with RE4F03A (1995–2000);
    • 🔧 32510-4M000 - for Sunny with RE4F04B (2000–2004).

    Among the analogues, the following have proven themselves well:

    • 🔹 Aisin (Japan) - a complete analogue of the original, price ~3,500 rubles;
    • 🔹 Febi (Germany) - budget option, ~2,200 rubles;
    • 🔹 Sachs — high quality, but more expensive (~4,000 rubles).

    When choosing, pay attention to: number of contacts in connector (on Sunny there are usually 4 or 6 of them), rod length (must match the old sensor), presence of an o-ring included.

    ⚠️ Attention: There are many counterfeits of original sensors on the market. Nissan. Signs of counterfeit: lack of a hologram on the packaging, unclear markings, low quality plastic. Buy only from trusted suppliers!

    Common replacement mistakes and how to avoid them

    Even experienced car owners sometimes make mistakes when replacing the selector lever position sensor. Here are the most common ones on Nissan Sunny:

    • ❌ Failure to comply with the position of the rod during installation. If the rod of the new sensor does not coincide with the selector lever, the automatic transmission will not work correctly.
    • ❌ Ignoring calibration. On boxes RE4F04B required after replacing the sensor reset adaptations through a diagnostic scanner.
    • ❌ Damage to the O-ring. Leads to oil getting into the sensor and its rapid failure.
    • ❌ Failure to check wiring. Often the problem lies not in the sensor, but in oxidized or frayed wires.

    To avoid problems: take a photo of the position of the old sensor before removal, use a torque wrench when tightening the bolts (torque - 8–10 N m), check the operation of all automatic transmission modes after replacement.

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    On Nissan Sunny with a mileage of more than 200 thousand km, it is recommended to replace not only the sensor, but also selector lever — it often backlashes and accelerates contact wear.

    FAQ: Frequently asked questions about the automatic transmission selector sensor

    Is it possible to drive with a faulty selector lever position sensor?

    Short term - yes, but this extremely dangerous. Without correct data from the sensor ECU does not know which mode is selected, which can lead to:

    • 🔴 Unpredictable gear shifts;
    • 🔴 Wheel locking when driving;
    • 🔴 Damage to the automatic transmission due to incorrect commands.

    If the sensor is completely out of order, it is better to call a tow truck.

    How much does it cost to replace a sensor at a service center?

    The cost of work depends on the region and the complexity of access to the sensor. On average:

    • 💰 Diagnostics: 500–1,000 rubles;
    • 💰 Sensor replacement: RUB 1,500–3,000;
    • 💰 Calibration (if required): RUB 1,000–1,500.

    Taking into account the price of the spare part, the total amount will be 5,000–10,000 rub..

    Can the sensor be repaired or is it just a replacement?

    In most cases the sensor beyond repair, since its body is sealed, and the contacts wear unevenly. However, sometimes it helps:

    • 🔧 Cleaning contacts with alcohol or WD-40;
    • 🔧 Replacement of oxidized wires;
    • 🔧 You can use a soldering iron to restore broken tracks (only for resistive sensors).

    But such repairs are a temporary solution. After 1-2 months the problem will return.

    Which sensor to choose for Nissan Sunny N16 with automatic transmission RE4F04B?

    Suitable for this model:

    • 🔹 Original: 32510-4M000 (~5,000 rub);
    • 🔹 Analogue Aisin: TSC-003 (~3,800 rub);
    • 🔹 Analogue Febi: 27303 (~2,500 rubles).

    Please note number of contacts - on N16 there should be 6 of them.

    What should I do if the automatic transmission jerks after replacing the sensor?

    This is a sign that:

    • 🔧 Sensor not calibrated (scanner required);
    • 🔧 Incorrectly installed rod (check alignment with the lever);
    • 🔧 Problems with wiring or connector;
    • 🔧 Defective torque converter or automatic transmission solenoids.

    Check first error codes and repeat the calibration.