Replacing the alternator on a Nissan Note: detailed instructions with photos and life hacks

Replacing the generator with Nissan Note - a task that every owner of this popular hatchback faces sooner or later. A faulty alternator can manifest itself in a variety of ways, from dim headlights to a completely drained battery overnight. Unlike more complex models Nissan (For example, Qashqai or X-Trail), in Note access to the generator is relatively simple, but there are some nuances that are important to know in advance.

In this article we will analyze the entire process from diagnostics to installation of a new generator, including the selection of spare parts, the necessary tools and common mistakes. We will pay special attention to models Nissan Note E11 (2006–2013) and E12 (2013–2020), as their designs have key differences. If you have never done auto electrical repairs, don’t worry: with the right approach, even a beginner can do it in 2–3 hours.

Signs of a generator malfunction on a Nissan Note

The first call is battery light on on the dashboard. But there are other symptoms that are often ignored:

• 🔋 The battery discharges overnight, despite a working battery (check the voltage at the terminals - there should be 12.6–12.8 V with the engine off).
• 💡 Headlights and interior lighting dim when the engine is idling.
• 🔊 Extraneous sounds (creaking, howling) from the generator are a sign of bearing wear.
• 📉 On-board voltage is lower 13.5 V with the engine running (checked with a multimeter).

On Nissan Note E12 with the system Start/Stop A faulty generator can cause frequent autostart failures. And on models with CVT low voltage leads to jerking of the box - this is due to the operation of the electronic control unit.

⚠️ Attention: If after starting the engine the voltage on the battery exceeds 15 V, this is a sign of a faulty voltage regulator (often it is changed separately, without the entire generator).

Before replacing the generator, be sure to check:

1. Alternator belt tension (should bend by 10–15 mm when pressed).
2. Condition of the battery terminals and ground wires (oxidation can simulate a generator malfunction).
3. The generator fuse is in the block under the hood (on Note E11 this is F30 (10A), on E12 — F20 (15A)).

Which generator to choose for Nissan Note: original vs analogues

Original generator from Nissan for Note E11 has an article number 23100-4M000 (90 A) or 23100-4M005 (110 A for versions with air conditioning). For E12 relevant 23100-JM00A (100 A) and 23100-JM00B (120 A). Original price - from 15,000 to 25,000 rubles, which seems overpriced to many.

Good analogues (tested by owners Note):

Brand	Article	Current (A)	Compatibility	Price (₽)
Denso	104210-4970	90–110	E11 (2006–2013)	8 500–12 000
Mitsubishi Electric	MR512877	100–120	E12 (2013–2020)	9 000–13 000
Bosch	0 986 041 920	90–110	E11, E12 (without Start/Stop)	7 800–11 500
Valeo	570273	100	E12 (with air conditioning)	8 200–12 000

When choosing an analogue, pay attention to:

• 🔧 Fastening: on E11 The generator is mounted on 2 bolts, on E12 - by 3 (one of them is a long hairpin).
• 🔌 Voltage regulator connector: in the original it is rectangular, in some analogues it is round (re-soldering will be required).
• 🔄 Direction of rotation: for Note suitable only right (clockwise when viewed from the pulley side).

⚠️ Attention: Generators from Nissan Micra K13 (article 23100-JM01A) are similar in appearance, but have a different excitation current and are not suitable for Note E12 with the system Start/Stop.

Tools and preparation for replacing the generator

To work you will need:

• 🔧 Set of sockets and ratchet wrenches (10 mm, 12 mm, 14 mm).
• 🔨 Extension and cardan joint for heads (access to the lower bolt of the generator is difficult).
• 🔪 Screwdriver with flat and cross blade (for removing protection and connectors).
• 🔌 Multimeter (to check the voltage before and after replacement).
• 🛠 Jack and stops (if wheel removal is required for access).
• 🧤 Gloves and rags (the generator is often covered with oil and dirt).

On Nissan Note E11 you can do without a pit or a lift, but for E12 It is advisable to have access from below - one of the fastening bolts is located there extremely inconveniently. If there is no hole, you will have to remove the right front wheel and fender liner.

Disconnect the negative battery terminal|Remove the engine protective cover (if equipped)|Loosen the generator belt tensioner|Disconnect the voltage regulator connector|Prepare the new generator for installation-->

Before starting work:

1. Disable negative battery terminal (this will prevent short circuit).
2. Take a photograph of the location of the alternator belt - on Note it often drives the air conditioner, so the tension pattern is important.
3. If the alternator changes due to a bearing, check the condition pulley — on worn-out copies it may play.

Step-by-step instructions for removing the generator

Dismantling process Nissan Note E11 And E12 similar, but there are differences in fastening. Let's consider a universal algorithm:

1. Loosen the belt tensioner.

   On E11 The tensioner is located to the right of the generator - loosen the nut 14 mm and slide the roller towards the engine. On E12 The tensioner is automatic (spring), so you have to remove the belt completely by turning the roller clockwise.

2. Disconnect the connectors.

   First, remove the chip from the voltage regulator (it is held on by a latch), then unscrew the nut 10 mm on the power wire (usually it is under the red cap).

3. Unscrew the generator mounts.

   On E11 — two bolts: upper 12 mm and lower 14 mm. On E12 a third bolt is added from the side of the cylinder block (access to it is difficult - you will need an extension).

4. Remove the generator.

   After unscrewing the bolts, the generator may “jam” due to corrosion. Don't hit it with a hammer - it's better to process the fasteners WD-40 and wait 10–15 minutes.

On Nissan Note E12 with engine HR12DE When removing the generator, be sure to check the condition of the sealing ring on the cylinder block - its damage leads to air leaks and an error P0171 (lean mixture).

What to do if the generator mounting bolt breaks?

If the bolt breaks off, do not try to drill it yourself - there is a high risk of damaging the threads in the cylinder block. It is better to contact a turner, who will carefully remove the fragment and cut a new thread with a repair size (for example, M8 instead of M7).

Installing a new alternator and tensioning the belt

Before installing a new generator:

• 🔧 Check the contents (the box should contain bolts, washers and sometimes a new pulley).
• 🧲 Test the diodes with a multimeter (in the “testing” mode, the resistance should be 400–600 Ohm in one direction and infinity in the other).
• 🛢 Lubricate the generator bearings lithium grease (especially if the machine is operated in high humidity conditions).

Installation proceeds in reverse order:

1. Attach the generator to its original location, but do not fully tighten the bolts.
2. Connect the power wire and the voltage regulator connector.
3. Put on the belt following the diagram (for E12 with air conditioning, the order is: crankshaft pulley → generator → power steering pump → air conditioning → tensioner).
4. Adjust the belt tension:
   • On E11: the belt deflection between the generator and the crankshaft should be 8–10 mm when pressed with force 10 kg.
   • On E12: The automatic tensioner does not require adjustment, but after installing the belt, turn the crankshaft 2 turns until the pulley is in the correct position.

⚠️ Attention: On Nissan Note E12 with the system Start/Stop After replacing the generator, it is necessary to reset the battery adaptation via a diagnostic scanner (for example, Launch X431). Without this, the system may incorrectly estimate the battery charge.

Typical mistakes when replacing a generator and how to avoid them

Even experienced craftsmen sometimes make mistakes that lead to repeated repairs. Here are the most common:

• ⚡ Reversed polarity when connecting the power cable. On Note “plus” always goes through the red cap, but some analogues have different markings. Always check the diagram!
• 🔩 Loose mounting bolts. Vibration from the engine quickly loosens the generator, which leads to a break in the ground wire. Tighten the bolts firmly 25–30 Nm.
• 🔄 Using a belt from a different model. For example, a belt from Micra 10 mm shorter and wears out quickly. For Note E11 fits 6PK1720, for E12 — 6PK1890.
• 💧 Dirt getting into the regulator connector. This leads to oxidation of contacts and voltage surges. Before connecting, clean the chip with alcohol.

Another common problem is noise after alternator replacement. Reasons:

• 🔊 The bearing of the new generator is “grinding in” (the noise should disappear after 100–200 km).
• 🔧 Incorrect belt tension (too much tension accelerates bearing wear).
• 🛠 Pulley defect (check its play by hand with the engine off).

Checking the operation of the generator after replacement

After installing a new generator, perform the following checks:

1. Visual inspection.

   Make sure that the belt is not distorted and that the generator does not touch adjacent parts (for example, the air conditioner pipe).

2. Voltage check.

   Connect the multimeter to the battery:

   • With the engine off: 12.6–12.8 V.
   • At idle speed: 13.8–14.5 V.
   • At 2000 rpm: 14.2–14.8 V.

Load test.

Turn on the headlights, heater and heated windows. The voltage should not drop below 13.5 V. If it sags until 12 V — the generator cannot cope (possibly a weak excitation current or a defect in the diode bridge).

Check for leaks.

Disconnect all consumers, turn off the engine and measure the leakage current (one multimeter probe on the “+” of the battery, the second on the removed terminal). Norm - up to 50 mA. If more, look for a “gluttonous” consumer (the voltage regulator is often to blame).

On Nissan Note E12 with the system Start/Stop After replacing the generator, an error may appear P0562 (low voltage on-board network). This is due to the fact that the ECU has not yet adapted to the new generator. The error should clear itself after 2-3 engine starting cycles.

FAQ: Frequently asked questions about replacing the alternator on a Nissan Note

Is it possible to drive with a faulty alternator if the battery is new?

Technically it is possible, but no further than 20–30 km. Modern cars (especially with Start/Stop) are heavily dependent on electronics. If the battery is discharged, the following will fail:

• 🔑 Immobilizer (the car will not start).
• 🚗 Electric power steering (the steering wheel will become very heavy).
• 📱 On-board electronics (e.g. sensors ESP or ABS).

In addition, deep discharge of the battery reduces its life by 2–3 times.

How much does it cost to replace a generator at a service station?

The cost of work depends on the region and model:

• Nissan Note E11: 1 500–2 500 ₽ (without removing the fender liner).
• Nissan Note E12: 2 500–4 000 ₽ (due to difficult access to the bottom bolt).
• With system Start/Stop: +1 000 ₽ for battery adaptation.

Replacing it yourself allows you to save money, but requires care - errors during connection can damage the ECU.

Which generator is better - original or analogue?

The original generator will last longer (resource 150–200 thousand km), but its price is often unjustified. Optimal choice:

• 🏆 For long-term use: Denso or Mitsubishi Electric (the resource is comparable to the original).
• 💰 Budget option: Bosch or Valeo (enough for 80–100 thousand km).
• ⚠️ Not recommended: generators NoName brands (eg Fenox or Starline) - often fail through 20–30 thousand km.

When purchasing an analogue, be sure to check the article number with Nissan catalog.

Do I need to change the alternator belt along with the alternator?

Not required, but recommended if:

• 📅 The belt is older than 4-5 years (rubber loses elasticity).
• 🔍 Cracks or delaminations are visible on it.
• 🔊 It whistles when the engine starts (a sign of slippage).

Belt cost for Note - total 500–800 ₽, and its breakage may lead to breakdown of the generator or power steering pump.

Why does the battery drain quickly after replacing the generator?

Probable reasons:

1. Faulty voltage regulator (even in a new generator!). Check the voltage at idle - if it is higher 14.8 V, the battery is boiling.
2. Poor ground contact between the generator and the body. Clean the point where the ground wire attaches to the engine (on Note it is located under the intake manifold).
3. High leakage current. Turn off the fuses one by one and find the “gluttonous” consumer (the alarm or radio is often to blame).
4. Incompatible battery. For Note E12 with Start/Stop needed AGM-battery (regular acid battery quickly degrades).