<em>Nissan Micra</em> air conditioning relay: how to check and replace without errors

Nissan Micra - a compact city car where the air conditioning system plays a key role for comfort. However, even in such a reliable car, the air conditioning relay can fail, leaving you without cool air in the cabin. In this article we will look at where the climate control relay is located in Micra K13 And K14, how to check it with a multimeter, what symptoms indicate a malfunction and how to replace the part yourself - with photographs, diagrams and prices for spare parts.

Feature Nissan Micra (especially models 2010–2020) - sensitivity of electronics to voltage drops. The air conditioning relay here often suffers from oxidation of the contacts or overheating, which leads to malfunctions of the compressor. If your air conditioner turns on every once in a while, hums or does not respond to the button at all A/C, the problem with 90% probability lies precisely in the relay or its circuits.

Where is the air conditioner relay located? Nissan Micra K13/K14

B Nissan Micra The air conditioning relay is located in fuse and relay mounting block, which is located inside the car - under the instrument panel on the driver's side. The exact location depends on the year of manufacture:

• 🔧 Micra K13 (2010–2017): the block is located to the left of the steering column, behind the plastic cover (fastened with latches). The air conditioner relay is usually designated as AC Relay or R17 (number may vary depending on configuration).
• 🔧 Micra K14 (2017–present): The unit has been moved closer to the center console, under the glove compartment. The relay is marked R12 or has a snowflake icon.

To get to the block you will need:

1. Turn off the ignition and remove the key.
2. Carefully pry off the unit cover with a flat screwdriver (the latches are fragile!).
3. There is a relay location diagram on the back of the cover - check it.

Important: in some versions Micra The air conditioner relay may be duplicated — one is responsible for powering the compressor, the second for the fan. If there are two relays on the diagram with the inscription A/C, check both.

Symptoms of a bad air conditioning relay

A/C relay Nissan Micra rarely fails suddenly - usually the failure is preceded by characteristic symptoms. Look out for the following signs:

• ❄️ Air conditioner turns on every other time - sometimes it works, sometimes it doesn’t, for no apparent reason.
• ⚡ When you press the button A/C audible relay click, but the compressor does not start.
• 🔊 Compressor buzzing, but does not rotate (a sound is heard as if something is blocking the mechanism).
• 💡 Lights up on the instrument panel air conditioner error (code P0530 or B1420 in diagnostics).
• 🔥 Relay warming up or smells like burnt plastic (a sign of a short circuit).

One of the most insidious symptoms is when the air conditioner is running only at high speeds (for example, when driving on the highway), but turns off at idle. This indicates insufficient voltage in the relay circuit, which can be caused either by a malfunction of the relay itself or by oxidation of the contacts in the fuse box.

⚠️ Attention: If the air conditioner comes on when you turn on main fuse (For example, F30 at 10A), do not replace it with a more powerful one! This may cause the wiring to catch fire. First check the relay and compressor circuit.

How to test an air conditioner relay with a multimeter

Checking the air conditioner relay Nissan Micra takes no more than 10 minutes and requires a minimal set of tools: a multimeter (in continuity or resistance measurement mode) and a screwdriver. Follow the step by step instructions:

1. Removing the relay: Remove the relay from the block (there is usually a contact diagram on the back). Please note the numbering of the legs: 85 And 86 - coil, 30 - general contact, 87 - normally open, 87a - normally closed (if any).

2. Coil continuity: Connect the multimeter probes to the contacts 85 And 86. The resistance of a working coil should be within 50–120 Ohm. If the device shows OL (break) or 0 (short circuit), relay is faulty.

3. Checking contacts: Apply voltage 12V to contacts 85 And 86 (you can use a power supply or battery). In this case, a click should be heard, and the contacts 30 And 87 close (check with a multimeter in continuity mode). If there is no short circuit, the relay must be replaced.

Contacts	Normal condition	When 12V is supplied	Symptom of malfunction
85–86	Resistance 50–120 Ohm	—	OL or 0 ohm
30–87	Open	Closed (resistance ~0 Ohm)	Do not close when voltage is applied
30–87a	Closed (if any)	Open	Do not open

If the relay is OK, but the air conditioner does not work, check:

• 🔌 fuse (usually F10 or F20 at 10–15A).
• 🔌 Wiring from the relay to the compressor (often frays near the radiator).
• 🔌 Freon pressure sensor (if the refrigerant level is low, the system is blocked).

Which air conditioner relay is suitable for Nissan Micra

A/C relay Nissan Micra - a standard part, but it is important to choose an analogue with suitable parameters. The original relay has an article number 25230-4M000 (for K13) or 25230-4M010 (for K14), but it can be replaced with analogues from other manufacturers. The main thing is a match in the following characteristics:

• 🔋 Rated voltage: 12V.
• 🔌 Switching current: not less than 30A (for compressor Micra 20–25A is enough, but it’s better to take it with a reserve).
• 🔄 Contact type: normally open (NO).
• 📏 Dimensions: standard housing for the mounting block (usually 28.5x19x15 mm).

Proven analogues of the original relay:

Manufacturer	Article	Price, ₽	Notes
Omron	G8JN-1A4-TR-DC12	450–600	Japanese quality, reliable contacts
Bosch	0 332 014 150	350–500	Suitable for most European cars
Hella	4RA 003 507-011	500–700	Reinforced contacts, long service life
Sontec	SR3211	200–300	Budget option, suitable for temporary replacement

When purchasing, pay attention to quality of contacts - cheap relays often have thin plates that quickly burn. If you choose between the original and the analogue, it is preferable Omron or Hella - they last longer than standard relays Nissan.

⚠️ Attention: In some trim levels Micra K14 a relay is installed with five-pin connector (additional diagnostic contact). If your relay has 5 legs, look for an analogue with the same pinout, otherwise the air conditioner will not turn on correctly via the CAN bus.

Step-by-step DIY replacement of the air conditioner relay

Replacing the air conditioner relay in Nissan Micra - a simple procedure that does not require special skills. You will need:

• 🔧 Flat screwdriver (for removing the block cover).
• 🔧 Tweezers or a special relay puller (optional).
• 🔧 New relay (tested with a multimeter).
• 🔧 Contact lubricant (for example, Liqui Moly Kontakt-Spray).

Sequence of actions:

1. Turn off the power: Remove the key from the ignition and remove the negative terminal from the battery (this will prevent a short circuit when replacing).
2. Remove the unit cover: Pry up the latches with a flat-head screwdriver. Be careful - plastic is fragile!
3. Remove the old relay: Gently pull it up, rocking it from side to side. If the relay is stuck, use tweezers.
4. Clean contacts: Inspect the sockets in the block for oxidation. If necessary, clean them with alcohol or special lubricant.
5. Install a new relay: Insert it until it clicks, making sure that the legs fit into the sockets without distortion.
6. Check the work: Connect the battery, turn on the ignition and start the air conditioning. If the compressor works, the replacement was successful.

If after replacing the relay the air conditioner still does not work, check:

• 🔌 fuse (may burn out if short circuited).
• 🔌 Freon pressure sensor (if the refrigerant level is low, the system is blocked).
• 🔌 Wiring from the relay to the compressor (often grinds or oxidizes).

Common mistakes when replacing relays and how to avoid them

Even such a simple operation as replacing a relay can result in new problems if common mistakes are made. That's what can't do when working with the air conditioner relay in Nissan Micra:

• 🚫 Ignore multimeter test: Not all relay faults are visible externally. For example, a coil break is not always accompanied by melting of the housing.
• 🚫 Install relays from other systems: The fan or starter relays may be identical in appearance, but have different characteristics (for example, switching current). This will lead to rapid failure.
• 🚫 Use force when installing: If the relay does not fit into the socket, do not press on it - check to see if the legs are bent. Forced installation may damage the contacts of the unit.
• 🚫 Forget about the battery terminal: If you do not turn off the minus, when removing the relay, a short circuit may occur, which will damage the fuse box.

Another common mistake is do not check the operation of the air conditioner immediately after replacement. If the new relay also does not work, the problem may lie in:

• 🔌 Broken wire between the relay and the compressor (check with a tester).
• 🔌 Compressor faults (seized bearing or burnt winding).
• 🔌 Fault in the climate control unit (requires diagnostics with a scanner).

What to do if the new relay immediately burns out?

If the installed relay immediately fails, this indicates a short circuit in the compressor circuit or a malfunction of the compressor itself. Do not install the following relay until you have checked:

1. Condition of the wiring from the relay to the compressor (are there any bare areas).

2. Compressor winding resistance (should be 2–5 Ohms; if 0 - short circuit).

3. Pressure in the air conditioning system (if the pressure is too high, the compressor is blocked, which can cause the relay to overload).

Cost of service work vs. self-replacement

If you are not confident in your abilities, you can entrust the replacement of the air conditioner relay to professionals. However, in the case of Nissan Micra this is not always justified from a financial point of view. Let's compare the costs:

Service	Service cost, ₽	On your own, ₽	Notes
Fault diagnosis	1 000–1 500	0 (if you have a multimeter)	The service may charge a fee even if the problem is not in the relay
Relay replacement	800–1 200	0	5 minutes of work, but services charge according to the tariff
Relay (original)	1 200–1 800	1 200–1 800	The price is the same, but the service may charge 20–30%
Relay (analog)	1 500–2 000	300–700	Services often supply the original or expensive analogues
Total	3 500–5 500	300–2 500	Save up to 80% when replacing yourself

Conclusion: if you have a multimeter and 20 minutes of free time, replacing the air conditioner relay Nissan Micra will cost 3–5 times cheaperthan in the service. The only case when you should contact a specialist is if, after replacing the relay, the air conditioner still does not work (diagnostics of the compressor or electronics will be required).

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

Is it possible to drive without an air conditioning relay?

Technically it is possible, but the air conditioning will not work. However, if the relay burns out due to a short circuit in the compressor circuit, driving without repair may lead to wiring overload and even fire. It is recommended to at least turn off the air conditioner fuse (F10 or F20) until the problem is eliminated.

Why does the air conditioning relay click but the compressor does not turn on?

This is a clear sign that the relay is working properly, but the problem is different:

• 🔌 Low freon pressure (the protection sensor is triggered).
• 🔌 Compressor fault (seized bearing or burnt coupling).
• 🔌 Broken wire between the relay and the compressor.

Check the pressure in the system with a pressure gauge and test the circuit from the relay to the compressor.

Which relay can be temporarily used instead of the original one?

In emergency cases, you can install a relay from cooling fan or fuel pump (if they are identical in size and current). However, it is not recommended to drive for a long time with such a relay - it is not designed for the compressor load and can quickly burn out. The best option is to buy an analogue from Omron or Hella (see table above).

How often should the air conditioning relay be replaced?

The air conditioner relay is not a consumable, and under normal conditions it serves 100,000–150,000 km. However, in Nissan Micra its resource is often reduced due to:

• 🔥 Voltage changes (especially with a weak battery).
• 💦 Moisture entering the fuse box (for example, after washing).
• 🔌 Oxidation of contacts (typical for cars over 5 years old).

If you notice that the air conditioner starts to turn on worse, check the relay every 20–30 thousand km (visual inspection and checking with a multimeter are sufficient).

Can a faulty A/C relay affect other vehicle systems?

In most cases, no, since the A/C relay operates independently. However, in Nissan Micra K14 with the system Intelligent Key malfunctions are possible immobilizerif a short circuit in the relay circuit damages the common CAN bus. Signs:

• 🔑 The car does not start from the start button.
• 🚗 An error appears on the panel Key System Error.

In this case, diagnostics with a scanner is required (for example, Launch X431) and wiring repairs.