Nissan Sunny FB15 — a reliable car, but even its key components fail over time. One of the most capricious is the **throttle position sensor (TPS)**, which directly affects the stability of the engine. If your Sunny started to twitch at idle, stall when changing gears or show an error P0120, with 80% probability this sensor is the culprit.

In this article we will look at how to independently diagnose a TPS malfunction on FB15, what tools will be needed for replacement, and why you should not save on original spare parts. And we’ll also reveal secret technique for checking a sensor without a multimeter, which is used by experienced mechanics.

What is TPS and how does it work in Nissan Sunny FB15

**The throttle position sensor (TPS)** is a potentiometer that converts the mechanical throttle position into an electrical signal to the ECU. B Nissan Sunny FB15 with engines GA15DE And GA16DE a **non-contact resistive type sensor** is used, which transmits data on the degree of damper opening in the range from 0 to 5 V.

The principle of operation is simple: when you press the gas pedal, the throttle opens and the sensor changes the resistance, sending a corresponding signal to the control unit. The ECU, in turn, adjusts the fuel supply and ignition timing. If the TPS starts to “lie”, the engine receives incorrect data - hence all the problems.

  • 🔧 Sensor type: resistive (film) or non-contact (magnetoresistive)
  • 📊 Signal range: 0.3–0.7 V (closed) / 4.0–4.7 V (fully open)
  • ⚡ Food: 5 V from the ECU (checked on pins 1 and 2 of the connector)

On FB15 The sensor is located directly on the throttle body and is secured with two Phillips screws. It is easily identified by its three-pin connector (sometimes four-pin on later versions).

Signs of a faulty TPS on a Nissan Sunny FB15

Symptoms of a TPS failure are often confused with ignition or fuel system problems. However there is 7 key signs, which directly point to the sensor:

  • 🚗 Floating speed at idle (from 500 to 1500 rpm)
  • 💥 Jerks during acceleration, especially at speeds of 40–60 km/h
  • 🛑 Engine stalling when changing gears or releasing gas
  • ⚠️ Check Engine with errors P0120, P0122, P0123
  • 🔥 Increased fuel consumption (10–15% above normal)
  • 🚦 Reaction delay pressing the gas pedal
  • 🔄 Spontaneous increase in speed up to 2000–2500 rpm

Problems are especially pronounced in damp weather or after washing the engine - moisture penetrates the sensor connector, causing short circuits. If symptoms appear periodically, the culprit is oxidized contact, and not the sensor itself.

⚠️ Attention: if the dashboard lights up Check Engine, don't ignore it! Driving for a long time with a faulty TPS leads to an over-enrichment of the fuel mixture and catalyst breakdown (replacement cost - from 20,000 ₽).
📊 How often do you check the sensors in your Nissan?
  • Once a year
  • Only when symptoms appear
  • Never checked
  • I monitor errors myself

How to check TPS on Nissan Sunny FB15 with a multimeter

Diagnostics of the sensor takes 10–15 minutes and requires a minimum set of tools: a multimeter (in voltmeter mode), a screwdriver and three jumper wires (“crocodiles”). Procedure:

  1. Removing the connector: disconnect the chip from the TPS by pressing the plastic lock.
  2. Power check: turn on the ignition (without starting the engine) and measure the voltage between pins 1 (+5V) and 2 (mass). Norm: 4.8–5.2 V.
  3. Signal check:
    • Connect the multimeter probes to pins 2 (mass) and 3 (signal).
    • Slowly open the throttle by hand (or have an assistant press the gas pedal).
    • The voltage should increase smoothly from 0.3–0.7 V (closed) until 4.0–4.7 V (fully open).
  • Checking for breaks: turn off the ignition and measure the resistance between contacts 1–3 and 2–3. Norm: 1–10 kOhm (depending on the position of the damper).
    • Parameter Normal value Symptom of malfunction
    Supply voltage (pin 1–2) 4.8–5.2 V <4.5 V or >5.5 V → problem in wiring or ECU
    Signal voltage (closed) 0.3–0.7 V <0.2 V or >1.0 V → sensor faulty
    Signal voltage (open) 4.0–4.7 V <3.5 V or >4.8 V → wear of the resistive layer
    Resistance (pin 1–3) 1–10 kOhm (smooth change) Break or short circuit → sensor replacement

    If, when the damper opens smoothly, the voltage jumps (for example, from 1.5 V to 3 V immediately), this means wear of the resistive layer - The sensor needs to be replaced. Also pay attention to the physical condition of the contacts: oxidation or green deposits indicate moisture ingress.

    Secret test method without a multimeter

    If you don’t have a tester at hand, you can check the TPS “by eye”:

    1. Remove the air pipe and visually inspect the damper.

    2. Ask an assistant to gently press the gas pedal.

    3. If the damper opens jerkily or gets stuck - the sensor is faulty.

    4. Also pay attention to the play of the damper axis: if it is more than 1–2 mm, the throttle assembly needs to be replaced.

    Original articles and analogues of TPS for Nissan Sunny FB15

    On Nissan Sunny FB15 Two types of sensors were installed: Hitachi (early versions) and Mitsubishi Electric (late). Original articles:

    • 🔹 22680-4M000 — Hitachi sensor (until 2002)
    • 🔹 22680-4M005 — Mitsubishi Electric sensor (after 2002 onwards)
    • 🔹 22680-4M010 - universal sensor for Asian markets

    The cost of the original is from 2500 to 4000 ₽. However, there are proven analogues that are not inferior in quality:

    Manufacturer Article Price, ₽ Features
    Bosch 0 280 122 004 1800–2200 Suitable for GA15DE/GA16DE, requires modification of the connector
    Hella 6XV 355 101-351 2000–2500 Complete analogue of the original, without adjustment
    ERA 550457 1200–1500 Budget option, resource ~50,000 km
    Blue Print ADT33003 1600–1900 Good price/quality ratio
    ⚠️ Attention: when buying an analogue, be sure to check connector and number of contacts! Sensors for 3 and 4 contacts not interchangeable. On FB15 with GA16DE 4-pin sensors were often installed (an additional contact for feedback).

    If you decide to save money and buy a non-original, give preference Hella or Bosch - they last longer than cheap Chinese clones. But the brand sensors Febi or Meat & Doria It’s better to avoid them: their resource rarely exceeds 30,000 km.

    Step-by-step instructions for replacing TPS on a Nissan Sunny FB15

    Replacing the sensor takes 20–30 minutes and does not require special skills. You will need:

    • 🔧 Phillips screwdriver (PH2)
    • 🔌 Flathead screwdriver (for connector lock)
    • 🧴 WD-40 or contact cleaner
    • 📦 New sensor (check that the O-ring is complete!)

    Disconnect the negative battery terminal

    Remove the air pipe from the throttle body

    Clean the work area from dirt (to avoid getting into the throttle)

    Prepare a new sensor and tools -->

    Step 1. Removing the old sensor

    1. Disconnect the negative terminal of the battery (required! This will reset the errors in the ECU).
    2. Disconnect the TPS connector by pressing the plastic clip.
    3. Unscrew the two sensor mounting screws (sometimes they stick - use WD-40).
    4. Carefully remove the sensor without damaging the O-ring.

    Step 2: Install a new sensor

    1. Clean the seat of old grease and dirt (use a lint-free cloth).
    2. Install a new O-ring (included with the sensor).
    3. Secure the sensor with screws, without over-tightening (tightening torque - 0.5–0.7 N m).
    4. Connect the connector until the latch clicks.

    Step 3: Calibration and Verification

    1. Connect the battery.
    2. Turn on the ignition for 10 seconds (the ECU automatically calibrates the sensor).
    3. Start the engine and check the idle speed (should be between 700-800 rpm).
    4. Take it for a test drive: accelerate to 60 km/h and check the smoothness of the ride.

    1. Disconnect the battery for 15 minutes.

    2. Reconnect and start the engine.

    3. Let it idle for 5–10 minutes (the ECU will “remember” the new parameters).-->

    Common mistakes when replacing TPS and how to avoid them

    Even experienced car owners make mistakes that lead to repeated sensor failure or engine malfunctions. Here TOP-5 misses and how to prevent them:

    • 🔧 Retightening the fastening screws → leads to deformation of the sensor housing. Solution: Use a torque wrench or finger tighten with minimal force.
    • ⚡ Ignoring Contact Cleaning → oxidized connectors give false signals. Solution: process contacts CRC Electronic Cleaner.
    • 🔄 Lack of calibration → The ECU continues to use the old parameters. Solution: After replacing, let the engine idle for 10 minutes.
    • 🚫 Dirt getting into the throttle body → causes the damper to jam. Solution: Cover the throttle hole with tape before removing the sensor.
    • 🔍 Buying a sensor without checking the article number → connector mismatch. Solution: check the number of contacts (3 or 4) and the shape of the connector.

    Another common mistake is use of sealant when installing the O-ring. This leads to silicone getting into the throttle assembly and subsequent repairs. The O-ring must fit tightly without additional funds!

    💡

    If after replacing the TPS there is an error P0120 does not disappear, the problem may lie in wiring (break or short circuit) or the ECU itself. In this case, diagnostics with a scanner is required (for example, Launch CReader).

    Prevention and increase in the resource of TPS

    Average sensor life per Nissan Sunny FB15 — 80,000–100,000 km. However, with proper care it can be extended up to 150,000 km. Here 5 simple rules:

    • 💧 Avoid engine washing under high pressure - water enters the TPS connector.
    • 🔌 Process contacts connector LIQUI MOLY Electronic-Spray once a year.
    • ⛽ Use quality fuel — bad gasoline accelerates wear of the resistive layer.
    • 🔧 Clean the throttle valve every 30,000 km (use Abro Carb Cleaner).
    • 🚗 Avoid sudden pressure on the gas - this reduces the life of the sensor.

    It is also recommended to check once every 20,000 km damper axis play. If it exceeds 1 mm, the throttle assembly requires repair or replacement. On FB15 Plastic axle bushings often wear out - they can be replaced separately (article no. 22685-4M000).

    If you operate the car in high humidity conditions (for example, in Primorye or St. Petersburg), install protective case to the TPS connector. You can make it yourself from a heat-shrinkable tube or buy a ready-made one (article 22688-4M000).

    FAQ: Frequently asked questions about TPS on Nissan Sunny FB15

    Is it possible to drive with a faulty TPS?

    Technically possible, but not recommended. A faulty sensor leads to:

    • Increased fuel consumption (up to +20%).
    • Overheating of the catalyst (risk of melting).
    • Unstable engine operation, which is dangerous in city traffic.

    If the sensor fails completely, the ECU will go into emergency mode, but engine power will drop by 30–40%.

    Which TPS is better - the original or the analogue?

    Original sensor (Hitachi/Mitsubishi) lasts longer (100,000+ km), but costs more. Analogues (Hella, Bosch) are cheaper, but their service life is 50,000–70,000 km. The choice depends on the budget:

    • Original — if you plan to drive a car for a long time.
    • Analogue - if you are selling a car in the near future.

    Among the analogues, the best option is Hella 6XV 355 101-351 (completely analogous in terms of characteristics).

    What should I do if, after replacing the TPS, the speed fluctuates?

    The reasons may be as follows:

    1. Poor quality sensor — check the signal voltage with a multimeter.
    2. Air leak — inspect the pipes for cracks (especially near the throttle).
    3. Dirty throttle valve - clean it Abro Carb Cleaner.
    4. ECU malfunction — diagnostics with a scanner is required.

    Start by checking intake tract tightness - this is the most common reason.

    Is it possible to repair the TPS or only replace it?

    Repair is only possible for resistive sensors (old models). Method:

    1. Disassemble the sensor (carefully so as not to damage the housing).
    2. Clean the resistive layer with alcohol.
    3. If there are breaks in the tracks, restore them with conductive glue (Permatex).

    However, such repairs short-lived (2–3 months). On FB15 With contactless sensors, repair is impossible - only replacement.

    What errors does the ECU give when there are problems with TPS?

    On Nissan Sunny FB15 most often found:

    Error code Description Probable Cause
    P0120 TPS circuit malfunction Broken wiring or sensor failure
    P0122 Low TPS signal level Wear of the resistive layer or oxidation of contacts
    P0123 High TPS signal level Short circuit or sensor damage
    P0505 Idle speed system error (related to TPS) Incorrect calibration after replacement

    For accurate diagnosis, use a scanner ELM327 or contact service.