A few years ago Nissan Primera P12 was the standard of reliability, but over time, even Japanese cars begin to require attention to detail. One of the most common problems in aging vehicles is the failure of electric windows. You may encounter a situation where the window goes down but does not go up, or the mechanism makes a characteristic grinding noise and then stops.
Ignoring such a malfunction can lead to more serious consequences: from the glass jamming in the open position during rain to a complete break in the cable and glass falling inside the door. Window lift repair - this is a task that even a novice car enthusiast can cope with if he has a basic set of tools and free time. The main thing is to understand the principle of operation of the mechanism and have access to spare parts.
The main causes of P12 window regulator malfunction
Before disassembling the door, it is necessary to accurately determine the cause of the breakdown so as not to change serviceable components. Most often, the problem lies in wear of the plastic rollers or breakage of the roller itself. steel cable. In cars Nissan Primera a cable mechanism is used, which over time is subject to corrosion and abrasion, especially if the door seals allow moisture to pass through.
The second common cause is failure of the electric motor. There are cases when the gearbox gear, made of plastic, simply grinds off and the motor spins idle. It is also worth checking the condition contact group in control buttons. Oxidation of contacts often leads to the fact that the glass rises only when the key is pressed hard or with a delay.
Preparing tools and necessary parts
For high-quality repairs, you will need a standard set of locksmith tools, but there are nuances specific to the P12 body. You definitely need to have a socket set including 10 mm and 8 mm, as well as a shaped screwdriver for removing plastic panels. Do not forget to prepare a new cable assembly or gear motor, depending on the identified malfunction.
Door design specifics Nissan Primera P12 requires care when dismantling the casing, as the plastic clips can become fragile after years of use. It is recommended to purchase a set of special pullers so as not to break the decorative elements of the interior. Also useful is grease for the guides and silicone spray for treating the seals after assembly.
- Doesn't rise at all
- Moves with difficulty/creaks
- Goes down but doesn't go up
- Works intermittently
Dismantling the door trim and removing the mechanism
Start by carefully removing the inner door card. Unscrew the two screws hidden under the decorative plugs in the area of the door handle and under the armrest. After this, pry the plastic clips around the perimeter of the card and pull it towards you to release the latches. Be careful: the backlight wire and the window lift button are connected to a common block; it must be disconnected before completely removing the trim.
Next, remove the waterproof polyethylene membrane. Often it is glued to bitumen mastic, so you will have to carefully tear it off, being careful not to tear it. If you are planning a renovation for many years, it makes sense to replace this membrane with a new one, since the old one can allow water inside the door. You now have full access to the window lift mechanism.
☑️ Dismantling the casing
Replacing the cable and gearbox: step-by-step instructions
If you determine that the problem is in the cable mechanism, replacing it will require complete removal of the assembly. Unscrew the three bolts securing the motor to the metal door and disconnect the power connector. Next you need to remove the guide holding the glass. IN Nissan Primera P12 The glass is attached to two bolts that need to be loosened so that the mechanism can be pulled out.
It's important to note that When replacing a cable, be sure to lubricate all pulleys and guides with special silicone grease, otherwise the new cable will quickly wear out. Disassemble the gear housing, if the problem is in the gear, and replace it with a metal one (if you find it on sale) or leave the plastic one, but with thorough lubrication. Reassemble in the reverse order, making sure that the cable does not twist.
What to do if the glass is warped?
If the glass is crooked after assembly, do not try to immediately tighten the fastening bolts. Loosen them, lower the glass all the way down, then lift it all the way up, align the position with the seal and only then tighten the bolts to the torque specified in the service manual.
Diagnostics of electrical parts and buttons
Sometimes the mechanism is working fine, but the problem lies in the electrics. Use a multimeter to check. Remove the power window control button block, which is located on the center console or in the door (depending on the configuration). Check for voltage at the contacts when you press a key. If the current does not flow, most likely the contacts inside the button are burnt.
Also check the fuse for the power windows. IN Nissan Primera it is located in the fuse box under the hood or in the passenger compartment. If the fuse is intact and there is no voltage coming to the motor, check the integrity of the wiring in the corrugation between the door and the body. There, wires often break due to constant opening and closing of the door.
Before installing a new power window button, wipe the contacts with alcohol and apply a thin layer of conductive grease or lithol to them to prevent future oxidation.
Table of common problems and solutions
To make it easier for you to navigate the problems, we have prepared a summary table of common failures. This will help you quickly find the right solution without unnecessary analysis.
| Symptom | Probable Cause | Solution |
|---|---|---|
| The motor hums, the glass does not move | The plastic gear of the gearbox is torn off | Replacing a gearbox or gear |
| The glass jams and a grinding noise is heard | Broken cable or misaligned rollers | Replacement of cable assembly, lubrication |
| The glass does not respond to the button | Fuse or button burnt out | Checking the fuse, replacing the button |
| The glass goes down but doesn't go up | Limit switch or relay malfunction | Electronics diagnostics, relay replacement |
Features of operation and prevention
After repairs, it is important to follow the operating rules so that the new mechanism lasts a long time. Regularly clean the rubber seals from dust and dirt. Sand that gets into the guides acts as an abrasive and quickly destroys the glass and mechanism. Use special sprays to care for rubber so that it remains soft and does not harden in the cold.
In winter, try not to turn on the power window if the glass is frozen to the seal. First, warm up the interior or carefully separate the glass from the rubber. If you notice that the motor is overloaded (humming loudly), immediately stop attempting to lift and check the mechanism. Ignoring signs of overload will lead to burnout of the motor windings.
Regular lubrication of the guides with silicone grease prolongs the life of the window lift mechanism by 2-3 times and prevents cable breakage.
⚠️ Warning: Never attempt to manually raise or lower the window by force when the mechanism is locked. This is guaranteed to lead to a broken cable or breakage of the plastic holders inside the door.
FAQ: Frequently asked questions
Is it possible to replace only the cable without changing the entire mechanism?
Theoretically yes, but in practice find a separate cable for Nissan Primera P12 difficult. Most often, assembled mechanisms are sold. Replacing only the cable requires very high assembly precision, and the risk of repeated breakage remains high.
How can you tell if your window motor is burnt out?
If when you press a button you don’t even hear a click or a faint hum of the motor, but there is voltage at the contacts, most likely the motor has burned out. There may also be a burning smell. In this case, the electric motor needs to be replaced.
Do I need to remove the entire glass when replacing the cable?
Yes, the glass must be removed, since the cable passes through special holders attached to the glass carriage. Without removing the glass, it is impossible to remove the mechanism and replace the cable.
How long does it take to repair a window regulator?
For an experienced technician, replacing the mechanism takes about 40-60 minutes. It may take 2-3 hours for a beginner, especially when carefully removing the sheathing and waterproof membrane.