Nissan Micra - a compact city car, which, despite its modest dimensions, is equipped with a full-fledged air conditioning system. However, over time, owners encounter problems with the climate control, and this is often due to air conditioner relay. This small part is responsible for turning on the compressor and protecting the electrical circuit from overloads, but if it fails, it can turn a summer trip into real torture.

In this article we will look at all aspects of air conditioning relay operation on Micra generations K13 (2010–2017) And K14 (2017–present), including its location, typical faults, diagnostic methods and step-by-step replacement instructions. We will pay special attention unique feature of the relay on Micra with engines HR12DE And HR16DE — its integration with the fuse box under the hood, which often confuses even experienced car owners.

Where is the air conditioner relay located? Nissan Micra?

The location of the relay depends on the year of manufacture and equipment of the vehicle. On most Micra K13 (2010–2017) and K14 (2017–present) it is set in fuse and relay box under the hood, but there are nuances:

  • 🔧 K13 (pre-restayl) - air conditioning relay (designated as A/C Relay) is located in the main fuse box next to the battery, under the plastic cover. Look for it near the cooling fan relay.
  • 🔧 K13 (restyle 2013+) And K14 - relay moved to additional block near the left headlight (driver's side), under the decorative trim.
  • ⚡ Micra with HR16DE engine - the relay can be integrated into Intelligent Power Distribution Module (IPDM), which requires special diagnostics.

To accurately identify a relay, pay attention to its markings. Original relay from Nissan has a number 25230-4M000 or 25230-4M00A (depending on the year). There is usually a diagram on the fuse box cover with the designation A/C Relay or Compressor Clutch Relay.

📊 Where is your air conditioning relay located?
  • In the main block under the hood
  • In the additional block near the headlight
  • In the cabin (behind the glove compartment)
  • I don't know, I didn't look

Symptoms of a bad air conditioning relay

A relay failure is not as obvious as, for example, a compressor failure. Here are the key symptoms that should alert you:

  • ❄️ Air conditioner won't turn on - when pressing a button A/C The light on the panel lights up, but the compressor does not activate (there is no characteristic click).
  • 🔄 Intermittent shutdown — the air conditioner operates jerkily and turns off spontaneously after 5–10 minutes.
  • 🔥 Relay overheating — when touching the relay body, strong heating is felt (normal temperature is up to 40–50°C).
  • 🚨 Fuse tripping - if the fuse blows along with the relay F17 (10A) or F20 (15A), the problem may be a short circuit.

It is important to distinguish a relay malfunction from problems with freon pressure sensor or compressor clutch. For example, if you hear a clicking sound when you turn on the air conditioner, but the compressor does not rotate, the clutch is to blame. If there is no click at all, check the relay and power circuits.

⚠️ Attention: On Micra K14 with the system NissanConnect a faulty relay can cause an error U1000 in the climate control unit. In this case, errors must be reset via a diagnostic scanner.

How to check the air conditioner relay for Nissan Micra

Relay diagnostics do not require special equipment - just a multimeter and a screwdriver. Follow this algorithm:

  1. Removing the relay: Disconnect the negative terminal of the battery, find the relay according to the diagram on the block cover and remove it with tweezers or your fingers.
  2. External inspection: Check the contacts for oxidation, melting or cracks. If the relay housing is swollen, it definitely needs to be replaced.
  3. Testing with a multimeter:
    • Set the multimeter to resistance test mode (ohmmeter).
    • Connect the probes to the terminals 85 And 86 (relay coil). Resistance must be within 50–120 Ohm.
    • Connect the probes to the terminals 30 And 87 (contacts). There must be resistance 0 ohm (closed).
  • Trigger check: Serve 12V to conclusions 85 And 86 (for example, from a battery). There should be a click and the contacts 30–87 shut up.

    • If the relay does not click or the coil resistance tends to infinity, it is faulty. Also worth checking air conditioner circuit fuse (usually 10A or 15A), which may burn out due to a short circuit in the relay.

    Remove the relay from the fuse box

    Check the external condition (cracks, melting)

    Ring the coil (pins 85–86)

    Call contacts (pins 30–87)

    Check operation when 12V is supplied-->

    Step-by-step replacement of the air conditioner relay

    If the diagnostics confirm that the relay is faulty, it must be replaced. The procedure takes no more than 10 minutes and does not require special skills. You will need:

    • 🔧 New relay (original 25230-4M000 or equivalent TYCO V23134, Bosch 0332019150).
    • 🔨 Flat screwdriver or tweezers for removing the relay.
    • 📸 Smartphone for photographing the connection diagram (in case the markings are erased).

    Replacement instructions:

    1. Disconnect the negative terminal of the battery (required! This will prevent a short circuit).
    2. Remove the fuse box cover under the hood (on Micra K13 it is secured with two latches).
    3. Locate the air conditioning relay according to the diagram on the back of the cover. On K14 it may be hidden under a decorative panel - you need to carefully pry it off with a screwdriver.
    4. Remove the old relay by pulling it up. If it gets stuck, don’t use force—it’s better to rock it from side to side.
    5. Install the new relay, making sure it is seated all the way. The contacts must be clean (if necessary, clean them with alcohol).
    6. Replace the unit cover and connect the battery.
    7. Check the operation of the air conditioner: turn on the ignition, press the button A/C and listen to whether the compressor works (there should be a click and a slight vibration).
    ⚠️ Attention: On Micra K14 with the system Auto A/C After replacing the relay, you may need to reset the climate control settings. To do this, hold down the button AUTO 10 seconds with the ignition on.
    💡

    If after replacing the relay the air conditioner still does not work, check freon pressure sensor (located on the high pressure pipe). When the refrigerant level is low, the system automatically blocks the compressor from turning on.

    Air conditioner relay wiring diagram Nissan Micra

    Understanding the diagram will help not only when replacing the relay, but also when diagnosing wiring problems. Below is a simplified diagram for Micra K13/K14:

    Relay contact Purpose Wire color (standard) Where does the wire go?
    85 Control minus (from the climate control unit) Black/yellow Controller A/C Amplifier
    86 Plus 12V (from fuse) Red/white fuse F17 (10A)
    30 Constant plus 12V (from battery) Yellow fuse F20 (15A)
    87 Compressor output Green/black A/C compressor clutch

    If, when checking with a multimeter on the contact 86 no 12V, the problem may lie in blown fuse or wire break. On Micra K14 also worth checking connector X11 block IPDM, which sometimes oxidizes.

    How to test the relay control circuit?

    To test the control circuit (pin 85), follow these steps:

    1. Turn on the ignition and press the A/C button.

    2. Using a multimeter in DC mode, measure the voltage between pin 85 and ground.

    3. If the climate control unit is working properly, it should be 0V (the unit “plants” the minus on the ground).

    4. If there is voltage (12V), the problem is in the control unit or freon pressure sensor.

    Common mistakes when replacing relays and how to avoid them

    Even such a simple procedure as replacing a relay can result in new problems if common mistakes are made. Here's what's most often done wrong:

    • 🔌 Ignoring the fuse: Many people change the relay without checking the fuse F17/F20. If it burns out, the new relay will also fail.
    • 🔄 Relay confusion: On Micra There is a similar cooling fan relay in the fuse block (Radiator Fan Relay). It's easy to confuse them!
    • 🛠️ Power replacement: If the relay cannot be removed, do not pull it with pliers - this can damage the contacts of the unit. It is better to use plastic tweezers.
    • 🔋 Poor polarity: When checking a relay with a multimeter, it is important to connect the probes correctly: 85–86 - coil, 30–87 — contacts.

    Another common mistake is purchasing a non-original relay of dubious quality. Cheap analogues (for example, nameless Chinese ones) often have low-quality contacts that quickly burn out. Optimal options:

    • 🏆 Original Nissan (25230-4M000) - reliability, but high price (~1500–2000 rubles).
    • 🥈 TYCO V23134 - high-quality analogue used on the conveyor Renault-Nissan.
    • 🥉 Bosch 0332019150 — a universal relay that matches the parameters.
    💡

    If after replacing the relay the air conditioner is unstable (turns on every other time), the problem may be oxidized contacts of the fuse box. Clean them with a special contact fluid (for example, Kontakt 60).

    Alternative reasons for an air conditioner not working

    If replacing the relay does not solve the problem, it is worth checking other elements of the air conditioning system. Here are the most likely culprits:

    Component Symptoms of a problem How to diagnose
    Freon pressure sensor Air conditioner does not turn on, error P0530 or P0533 Test the sensor with a multimeter (the resistance should change as the pressure changes)
    Compressor clutch There is a click, but the compressor does not rotate Checking the voltage at the clutch (should be 12V with A/C on)
    Climate control unit Does not respond to button presses, errors U1000, B1422 Diagnostics with a scanner or checking the power supply of the unit
    Freon leak The air conditioner turns on but does not cool Checking the pressure with a pressure gauge or UV lamp (with fluorescent dye)

    On Micra K14 with the system NissanConnect Air conditioner malfunction may be due to software glitch control unit. In this case, resetting the settings or flashing the firmware via the diagnostic connector helps.

    ⚠️ Attention: If the cooling fan operates at maximum speed when you turn on the air conditioner, this may indicate short circuit in relay circuit or a malfunction of the evaporator temperature sensor.

    FAQ: Frequently asked questions about the air conditioner relay Nissan Micra

    Is it possible to drive without an air conditioning relay?

    Technically yes, but the air conditioning won't work. However, prolonged driving with a faulty relay can lead to circuit overload and failure of the climate control unit. If the relay is “stuck” in the closed state, this threatens compressor overheating.

    What is the difference between the relays on K13 and K14?

    On Micra K13 (until 2013) a relay with open contacts (number 25230-4M000), and on K14 — with sealed housing (25230-4M00A). They are interchangeable, but a sealed relay lasts longer in high humidity environments.

    Why does a new relay burn out quickly?

    This happens due to:

    • 🔥 Short circuit in the compressor circuit (check the clutch).
    • 💧 Moisture getting into the fuse box (especially important for K13).
    • ⚡ Faulty freon pressure sensor (it can send false signals to the control unit).

    Can I fix the relay myself?

    In most cases, no. The relay is non-separable, and attempts to disassemble it lead to damage to the contacts. Exception - contact oxidation, which can be cleaned with alcohol or a special liquid. If the coil burns out or the contacts burn out, the relay must only be replaced.

    Where to buy an original relay for Micra?

    The original relay can be ordered:

    • 🛒 From an official dealer Nissan (code 25230-4M000).
    • 🌍 On AliExpress or eBay (search by code, but be careful of fakes).
    • 🔧 In auto electrical stores (for example, AutoSpetsCenter, Exist.ru).

    The price of the original is from 1500 rubles, analogues are from 300 rubles.