Nissan Almera Classic (N16) is a reliable car, but even it has electrical problems over time. One of the most insidious malfunctions is related to throttle relay - a small but critical element that affects the stability of the engine. If your Almera started to twitch during acceleration, stall at idle or give an error message P0505 (malfunction of the idle speed control system), this relay may be the culprit.

Unlike the throttle position sensor (TPS), which often fails, the relay is responsible for damper motor power supply. If it breaks, the ECU loses control over the air supply and the engine goes into emergency mode. In this article we will look at how to independently diagnose the problem where the relay is located in Almera Classic, and how to replace it without contacting service.

What is a throttle relay and why is it needed?

The throttle relay is electromagnetic switch, which controls the voltage supply to the damper drive. B Nissan Almera Classic (2006–2012) with engines QG15DE And QG16DE it performs two key functions:

  • 🔌 Circuit protection from overloads and short circuits.
  • ⚡ Voltage stabilization for smooth operation of the damper motor.
  • 📡 Signal transmission from the ECU to the actuator.

Without a working relay, the electronic control unit (ECU) will not be able to correctly regulate the opening of the damper, which leads to:

  • 🚗 Jerks when driving at low speeds.
  • 🛑 Spontaneous engine stop at idle.
  • ⚠️Lamp lights up Check Engine with errors P0505, P0506 or P0507.

Unlike the throttle position sensor (TPS), which can be checked with a multimeter, the relay is diagnosed differently - its operation is assessed by clicking sound when turning on the ignition and engine response to pressing the gas pedal.

📊 What engine does your Nissan Almera Classic have?
  • QG15DE (1.5 l)
  • QG16DE (1.6 l)
  • Other
  • I don't know

Signs of a bad throttle relay

Symptoms of a relay failure are often confused with a malfunction of the throttle assembly itself or the TPS. However there are several unique features, which directly indicate a problem with the relay:

⚠️ Attention! If, when you turn the ignition key, you do not hear a characteristic click of the relay (in the fuse box), this is the first signal about its failure. B Almera Classic The throttle relay usually clicks at the same time as the fuel pump relay.
  • 🔥 The engine stalls immediately after starting (especially in cold weather).
  • 📉 Idle speed “floats” from 500 to 1500 rpm without pressing the gas pedal.
  • 🚦 The car jerks when changing gears (in the case of a manual transmission) or when accelerating (in an automatic transmission).
  • 🔧 Error P0505 (Idle Control System Malfunction) appears even after a reset and returns after 10–20 km.

It is important to distinguish a relay malfunction from problems with throttle assembly. For example, if the damper is dirty, the symptoms will be similar, but the error in this case is usually different - P0120 or P0122. But if the relay “sticks”, then the speed can hang at 2000–2500 rpm and do not drop even after stopping the car.

Symptom Probable Cause How to check
Engine stalls at idle Throttle relay or TPS Swap the relay with a similar one (for example, with a fan relay)
The speed “freezes” at 2000 rpm Relay or damper jamming Check the relay clicks when you turn on the ignition
Jerks during acceleration Unstable power supply from relay Measure the voltage at the contacts of the throttle assembly
Error P0505 Relay or wiring Diagnostics with a scanner and checking the circuit with a multimeter

Where is the throttle relay located in Nissan Almera Classic?

B Nissan Almera Classic The throttle relay is located in fuse and relay box, which is located in the cabin under the instrument panel on the driver's side. Exact location:

  1. Open the driver's door and remove the plastic cover under the steering wheel (it is secured with two latches).
  2. Locate the black plastic fuse and relay box (located to the left of the steering column).
  3. Throttle valve relay Almera Classic usually installed in the third row, second slot from the right (number may vary depending on year of manufacture).

To avoid mistakes, refer to the diagram printed on the inside of the block cover. The throttle relay is often referred to as Idle Control Valve Relay or ETC Relay (Electronic Throttle Control).

What does the throttle relay look like?

It is a standard 4-pin relay marked 25A 12V (sometimes 20A). The body is usually black or dark gray and may have an inscription on the top NISSAN 25120-4M000 or similar.

If you are not sure which relay is responsible for the throttle valve, you can use the swapping method: temporarily swap it with the relay cooling fan (it is the same in size and contacts). If after replacement the symptoms disappear, the problem is in the throttle relay.

How to test the throttle relay with a multimeter?

Before replacing the relay, you should make sure that it is really faulty. For this you will need multimeter and a screwdriver. The check is performed in two stages:

Check for a clicking sound when turning on the ignition|

Measure the resistance of the relay coil (should be 50-120 ohms)|

Ring the contacts in the “on” position (there should be a short circuit) |

Make sure that the relay receives 12V from the ECU -->

Step 1: Checking the Relay Coil

Switch the multimeter to resistance measurement mode (200 Ω) and connect the probes to the contacts 85 and 86 (contact numbers are usually indicated on the relay body). A working relay should show a resistance in the range 50–120 Ohm. If the device shows 0 (short circuit) or 1 (break) - the relay is faulty.

Stage 2: Checking the functionality of the contacts

Connect the multimeter to dialing mode (diode) to contacts 30 and 87. When voltage is applied to the winding (pins 85 and 86), a characteristic clicking sound should be heard, and the multimeter will show 0 Ω (closing contacts). If this does not happen, the relay must be replaced.

Also check if it arrives 12V to contact 30 relay when the ignition is on. If there is no voltage, the problem may be in the fuse (usually 10A or 15A, is responsible for the throttle circuit) or in the wiring.

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If you don't have a multimeter handy, you can temporarily install a known-good relay (for example, from a fan or fuel pump) and see if the symptoms go away.

Step-by-step instructions for replacing the throttle relay

Replacing the relay in Nissan Almera Classic takes no more than 5 minutes and does not require special tools. All you need is a new relay and a flathead screwdriver (to remove the fuse box cover).

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Before replacing the relay, be sure to reset the negative terminal of the battery for 5-10 minutes to clear errors in the ECU.

  1. Disconnect the battery.

    Remove the negative terminal to avoid short circuits when working with electrical equipment.

  2. Remove the fuse box cover.

    It is secured with two plastic latches. Use a screwdriver to pry it off and carefully remove it.

  3. Locate the throttle valve relay.

    Refer to the diagram on the back of the cover or use the rearrangement method (described above).

  4. Remove the old relay.

    Gently pull it up, rocking it slightly from side to side. Do not use excessive force; the contacts may bend.

  5. Install a new relay.

    Insert it all the way, making sure the pins line up with the connector.

  6. Connect the battery and check the engine operation.

    Start the car and let it idle for 2-3 minutes. The speed should be stable (800–900 rpm).

⚠️ Attention! After replacing the relay it may be necessary throttle adaptation. To do this:

1. Stop the engine.

2. Turn on the ignition for 10 seconds (do not start the car).

3. Turn off the ignition and wait 20 seconds.

4. Start the engine and let it run for 1-2 minutes.

Cost of relays and analogues for Nissan Almera Classic

Original throttle relay for Nissan Almera Classic has an article number 25120-4M000 or 25120-4M005 (depending on the year of manufacture). Its price in official dealers is 1200–1800 rubles. However, you can save money by purchasing an analogue from trusted manufacturers.

Manufacturer Article Price, rub. Notes
Nissan (original) 25120-4M000 1200–1800 Better quality, but more expensive
Bosch 0 332 209 150 400–600 Reliable analogue, fits the parameters
Hella 4RA 003 553-121 500–700 Good quality, long service life
ERA 550107 250–400 Budget option, but fakes are possible

When purchasing, pay attention to rated current - the relay must be designed for 20A–25A. Cheap Chinese analogues (for example, nameless ones from AliExpress) often fail after 1–2 months, so it is better to give preference to proven brands.

If you are not sure about the choice, you can take the relay with you to the store and compare it with the options offered. The main thing is to match:

  • 🔌 Contact location (4 pins: 85, 86, 87, 30).
  • 📏 Case dimensions (standard 12V relay).
  • ⚡ Rated current (at least 20A).

Common mistakes when replacing relays and how to avoid them

Even something as simple as replacing a relay can result in new problems if mistakes are made. Here are the most common ones:

  • 🔧 Using a relay with a different rating.

    For example, installing a relay on 10A instead of 25A will lead to its rapid burnout.

  • 🔌 Incorrect connection of contacts.

    If you confuse 87 And 30, the relay will not operate.

  • 📉 Ignoring throttle adaptation.

    After replacing the relay, the ECU may not immediately “pick up” the new parameters, which will lead to floating speed.

  • ⚠️ Buying a fake.

    Cheap relays often have poor quality contacts that oxidize after a few months.

To avoid problems:

  1. Before purchasing, check the relay for functionality (if possible).
  2. After installing the new relay be sure to clear errors through a diagnostic scanner or by disconnecting the battery.
  3. If the problem remains after replacing the relay, check fuse (usually F10 or F15 in the block) and wiring from the ECU to the throttle body.
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If after replacing the relay the engine still stalls, check the throttle assembly for mechanical damage or contamination. Often the problem lies in the throttle itself, and not in the relay.

FAQ: Frequently asked questions about the throttle relay

Is it possible to drive with a faulty throttle relay?

Technically possible, but not advisable. The engine will operate in emergency mode, which will lead to:

  • Increased fuel consumption (up to +2–3 l/100 km).
  • Jerking during engine acceleration and braking.
  • There is a risk of stalling at an intersection or in a traffic jam.

If the relay has completely failed, the throttle valve may jam in the open or closed position, which can lead to loss of control of the vehicle.

How to distinguish a relay failure from a throttle assembly failure?

Do a simple test:

  1. Remove the air duct pipe and manually open the damper (with the ignition off). It should move smoothly, without jamming.
  2. If the flapper is clean and moves freely, the problem is likely in the relay or wiring.
  3. If the valve is dirty or sticking, clean the throttle assembly.

Also note the errors: P0505 more often indicates a relay, and P0120 — to the throttle position sensor (TPS).

Which relay can be used instead of the original one?

Any 4-pin relay will work 20A–25A with a similar contact group. For example:

  • Cooling fan relay (from the same unit).
  • Fuel pump relay (if identical in size).
  • Universal relays from Bosch or Hella (see table above).

The main thing is that the relay is normally open (that is, contacts 30 and 87 close only when voltage is applied to the winding).

Do I need to reset the throttle adaptation after replacing the relay?

In most cases Nissan Almera Classic spontaneously performs adaptation after replacing the relay. However, if the idle speed remains unstable, perform the procedure manually:

1. Заглушите двигатель.

2. Включите зажигание на 10 секунд (не заводите автомобиль).


3. Выключите зажигание на 20 секунд.


4. Заведите двигатель и дайте ему поработать 1–2 минуты.

If this does not help, you may need diagnostics with a scanner (for example, Launch CReader) to reset errors.

Why does a new relay quickly fail?

If the relay burns out after 1–2 months, the reasons may be as follows:

  • 🔥 Short circuit in the throttle assembly circuit. Check the wiring from the ECU to the throttle body for exposed wires.
  • 💧 Moisture has entered the fuse box. This leads to oxidation of the contacts.
  • ⚡ Unstable voltage in the on-board network. Check the generator and battery.
  • 🔧 Poor quality relay. This is especially true for cheap Chinese analogues.

If the relay burns out repeatedly, be sure to check throttle assembly — perhaps there is mechanical damage, due to which the damper motor consumes increased current.