Nissan Primera P12 (2002–2008) is a reliable sedan, but even its starter wears out over time. If you hear clicks when you turn the key, but the engine does not turn over, or the starter works “every once”, it’s time to check it. Dismantling the unit on P12 has nuances: a cramped engine compartment, inconvenient access to the bottom bolt and the risk of damaging the wiring. In this article - step by step analysis taking into account the characteristics of gasoline (QR20DE, QR25DE) and diesel (YD22DDTi) versions.

We will not advise you to “blindly follow the instructions” - instead, we will analyze three critical points that even experienced craftsmen are silent about: how to avoid breaking the positive wire, why you can’t remove the starter without disconnecting the battery, and how to unscrew the bottom bolt without a hole. They also provided a table of starter compatibility for different modifications Primera P12 and FAQ on troubleshooting.

Preparation: Tools and Safety Precautions

Before you climb under the hood, make sure you have:

  • 🔧 A set of sockets with an extension (required 14 mm head for the bottom bolt)
  • 🔨 Ratchet wrench and wrench (for access in tight spaces)
  • 🔌 Multimeter (to check the voltage on the contacts)
  • 🧲 Magnetic holder (so as not to drop the bolts into the pallet)
  • 🔦 Flashlight with bracket (underhood lighting)

Security is not a formality. Disconnect the negative battery terminal First of all: even with the ignition off, voltage remains on the starter. If you are working on a pit or lift, secure the machine with the handbrake and chock the rear wheels. On diesel Primera P12 (YD22DDTi) additionally remove the air intake - it interferes with access to the starter.

⚠️ Attention: On models with automatic transmission, before removing the starter necessarily remove the terminal from the selector lever position sensor (located on the box next to the starter). Otherwise, if the contacts are accidentally closed, the transmission control unit may burn out.
📊 What engine does your Primera P12 have?
  • QR20DE (2.0 l, petrol)
  • QR25DE (2.5 l, petrol)
  • YD22DDTi (2.2 l, diesel)
  • Other

Starter localization and protection removal

Starter on Primera P12 located to the right of the engine (if viewed in the direction of travel), between the cylinder block and the gearbox. On gasoline versions it is partially closed by the intake manifold, on diesel versions it is partially closed by a turbine and intercooler. To get to the mounting bolts:

  1. Remove the plastic engine cover (held on by 4 clips).
  2. Unscrew the fastening bolts heat shield starter (2 bolts of 10 mm).
  3. On diesel models, remove the air duct from the turbine to the intercooler (loosen the clamps and remove the mass air flow sensor).

After removing the protection, you will see the starter itself - a black cylindrical body with two thick wires (positive from the battery and control from the ignition switch). Don't pull the wiresso as not to tear off the terminals!

Turning off the electrics: procedure

At the starter Primera P12 three wires:

  • 🔴 Thick red — plus from the battery (constant voltage 12V).
  • 🟢 Slim green/black — control signal from the ignition switch.
  • ⚫ Black — weight (may be absent on some versions).

Disabling procedure:

  1. Loosen the nut on thick positive wire (10 mm wrench), but do not remove it completely - first disconnect the control wire.
  2. Snap off the plastic clip on thin wire (a flathead screwdriver may be required).
  3. Only after this completely unscrew the nut of the positive wire and remove it, insulating the end with electrical tape.
⚠️ Attention: If you first remove the positive wire and then accidentally touch it to the housing, a short circuit will occur. This may disable fuse box or even the engine ECU.
Modification Primera P12 Starter type Original article number Analogs (brand)
QR20DE (2.0 l, petrol) Geared, 1.4 kW 23300-4M500 Bosch 0 001 108 005, Denso DSR2014
QR25DE (2.5 l, petrol) Geared, 1.7 kW 23300-4M501 Valeo 438083, Hitachi SR4209
YD22DDTi (2.2 l, diesel) Spur, 2.0 kW 23300-ED000 Mitsuba M000T57401, Delphi DS1203N

Dismantling the starter: step-by-step analysis

Now let's move on to the fasteners. Starter on Primera P12 fixed two bolts:

  • 🔝 Top bolt — accessible from above (14 mm head).
  • 🔽 Bottom bolt - hidden under the box, harder to get to.

Instructions:

Loosen the top bolt 2-3 turns|Unscrew the bottom bolt completely (use an extension)|Take the starter down, tilting it at an angle of 30°|Check the integrity of the Bendix gear before installing the new one-->

  1. Loosen up top bolt 2-3 turns (do not unscrew completely!).
  2. For bottom bolt use an extension with a universal joint. On gasoline models you can climb up from above, on diesel models you will have to work from below (you need a pit or a lift).
  3. After unscrewing both bolts, carefully pull out the starter. down, tilting it at an angle of 30° (otherwise it will get caught on the box body).

If the starter does not work, check:

  • 🔧 Did you remember to unscrew the bolts completely?
  • 🔌 Is the positive wire clinging to the bracket?
  • 🛠️ Is the Bendix gear stuck to the flywheel (relevant for cars with mileage >150 thousand km).
What to do if the bottom bolt does not come off?

If the bolt is stuck, try:

1. Treat it with a penetrating lubricant (for example, Liqui Moly LM-40) and wait 15 minutes.

2. Use an impact wrench with a 14 mm socket (but do not overdo it - there is a risk of stripping the thread).

3. Heat the bolt with a hair dryer (up to 100–150°C) - the metal will expand and weaken corrosion.

4. As a last resort, drill out the bolt and cut a new thread (you will need an M8×1.25 tap).

Diagnostics of a removed starter

Before you run for a new starter, check the old one. Often the problem lies in:

  • 🔋 Brushes - wear up to 50% requires replacement.
  • 🔄 Bendix — the gear should rotate freely in one direction and be blocked in the other.
  • 🧲 Solenoid relay — when 12V is applied, a clear click should be heard.
  • 🔌 Winding — the resistance between the case and the terminals must be >10 kOhm (checked with a multimeter).

How to check the solenoid relay:

  1. Connect plus from the battery to the relay control terminal, and minus - to the starter housing.
  2. If the relay is working properly, a click will be heard and the Bendix gear will move out.
  3. If there is no click, the relay needs to be replaced. If there is a click, but the gear does not come out, the problem is in the bendix.

To check the winding, use a multimeter in ohmmeter mode:

  • Resistance between terminal 50 (control wire) and housing - ∞ (break).
  • Resistance between terminal 30 (plus from the battery) and the body - 0.1–0.5 Ohm.
💡

If the starter turns, but does not engage the flywheel, the problem is in the bendix. If it clicks but does not turn, the solenoid relay or brushes are to blame. These faults can be eliminated by repair; it is not necessary to buy a new starter.

New starter installation and assembly

Installation is carried out in reverse order, but there is 3 critical moments:

  1. Lubricate the Bendix gear thin layer molybdenum grease (For example, Liqui Moly Molykote Longtime Grease). This will extend the life of the mechanism.
  2. Tighten the bolts crosswise: first lower (torque 35–40 Nm), then upper. This way the starter will sit smoothly, without distortions.
  3. Check the clearance between the gear and flywheel - he must be 0.5–1.5 mm. If the gap is larger, the bendix will slip.

After installation:

  • Connect control wire (thin) first - this way you will avoid accidental short circuit.
  • Tighten the nut positive wire with a torque of 10–12 Nm (do not overtighten, otherwise you will break the thread).
  • Before the first launch Crank the engine 2–3 times by hand (with a wrench on the crankshaft pulley bolt) so that the Bendix gear sits in place.
⚠️ Attention: On diesel Primera P12 after replacing the starter it may light up Check Engine due to a malfunction of the crankshaft position sensor. Reset the error using the scanner (code P0335) or disconnect the battery for 10 minutes.

Common mistakes and how to avoid them

Even experienced craftsmen sometimes make mistakes when working with a starter. Primera P12. Here TOP-5 errors and their consequences:

Error Consequences How to avoid
Didn't disconnect the battery before work Short circuit, blown fuse box Shoot negative terminal first
Tightened the fastening bolts Thread failure in the box body Use a torque wrench (torque 35–40 Nm)
Didn't check the bendix clearance Slippage, accelerated gear wear Measure the gap with a feeler gauge before installation
Connected the wires in the wrong order Contact burnout, starter failure First the thin manager, then the thick plus one
Bendix gear not lubricated Accelerated wear, noise when starting Use molybdenum grease

Another typical problem is The starter turns, but the engine does not start. Reasons:

  • 🔧 Weak contact on the positive wire (check the tightness of the nut).
  • 🔋 Discharged battery (voltage below 11.5V is not enough to rotate the flywheel).
  • 🛠️ Bendix slipping (the gear does not engage the flywheel).

FAQ: questions about removing the starter on Nissan Primera P12

Is it possible to remove the starter without a pit?

Yes, but only on petrol versions (QR20DE, QR25DE). To access the bottom bolt, use extension with universal joint and work from above. On diesel Primera P12 It’s difficult to do without a pit or a lift - the turbine and intercooler get in the way.

How long does it take to replace a starter?

On average 1.5–2.5 hoursif there are no complications. On diesel models it can take up to 3-4 hours due to the need to remove air ducts and heat shields. The service estimates the work at 2–3 standard hours.

Which starter is better - original or analogue?

Original starters (23300-4M500 etc.) last longer, but cost 2–3 times more than analogues. From the non-original we recommend:

  • 🔋 Bosch - reliability, but high price.
  • 🔄 Denso — optimal price/quality ratio.
  • 💰 Valeo - a budget option, but the resource is lower.

For diesel Primera P12 is it better to take the original or Mitsuba - cheap analogues often cannot withstand high loads.

What to do if after replacement the starter does not turn?

Check:

  1. Are you connected? both wires (manager and power).
  2. Are the terminals on the solenoid relay reversed?
  3. Voltage at terminal 30 (should be 12V when turning the key).
  4. Integrity fuse F30 (10A) in the block under the hood.

If everything is in order, but the starter is silent, there may be a defect in the new unit (defective solenoid relay or winding).

Does the starter need to be lubricated during installation?

Yes, but Bendix gear only And bushings (if they are collapsible). Do not lubricate:

  • 🚫 Solenoid relay contacts.
  • 🚫 Brushes and commutator (this will cause them to wear out quickly).

Use high temperature grease (For example, Molykote G-Rapid Plus), since the starter heats up to 80–100°C.