The initial position of the key in the cylinder is a critical moment for starting the car engine Nissan Almera Classic. If your car won't start, it's often not the battery or starter that's to blame, but rather wear and tear on the internal components of the locking mechanism. Exactly ignition switch contact group is responsible for supplying power to the starter, fuel pump and engine management system.
Owners of Japanese sedans Nissan face the problem of oxidation or melting of contacts after several years of operation. This leads to the fact that when you turn the key to the “Start” position, the car simply does not respond, or the engine stalls immediately after starting. Understanding the structure of the unit and the ability to replace it correctly can save you a significant amount at a car service center.
Signs of contact group malfunction
Symptoms of failure may manifest differently depending on the degree of wear of the contacts inside the unit. Most often, the driver notices that when the key is turned to the “Ignition” position (position II), not all of the indicators on the instrument panel light up, but only some of the lights. This is a clear sign that ignition contacts have high contact resistance or are completely broken.
A more critical situation occurs when trying to start the engine. If you turn the key to the “Start” position (position III), but the starter does not turn, and only a quiet click or silence is heard, the problem is almost certainly in the contact group. In rare cases, the engine may start, but when the key is released it immediately stalls, since the power supply circuit to the ECU and the fuel pump is not kept in a closed state.
Sometimes the malfunction is accompanied by sparking or even a burning smell from under the instrument panel. This indicates that the contacts began to melt under load due to poor fit. In such a situation, the operation of the car Nissan Almera Classic is unacceptable, as there is a risk of fire in the wiring.
Design and principle of operation of the unit
Structurally, the ignition switch consists of two main parts: a mechanical cylinder (cylinder) and an electrical contact group. The cylinder physically opens the lock and turns the rod, and the electrical part converts this mechanical movement into closing power circuits. In the model Nissan Almera Classic A reliable, but vulnerable to current overloads connection circuit is used.
A significant current passes through the contact group, especially when the engine starts, when the starter consumes hundreds of amperes. If the cross-section of the wires is selected incorrectly or the contacts are oxidized, excess heat is generated. This is why in some cases the housing melts ignition switch connector and burning of the contacts themselves inside the plastic block.
It is important to understand that replacing only the mechanical part (cylinder) will not solve the problem if the electrical part has already failed. It is necessary to check the integrity of the contacts specifically in the electrical section, which is mounted on the side of the lock cylinder. Often repairs involve a complete replacement of the entire unit, since soldering individual contacts is difficult and unreliable.
Circuit Diagnostics and Testing
Before disassembling the steering column, it is worth conducting preliminary diagnostics using a multimeter. You need to check the presence of voltage on the output wires of the contact group in different key positions. To do this, you need to remove the plastic trim of the steering column and find the connector connected to the lock block.
If there is voltage at the input (from the battery), but it disappears at the output when you turn the key, the contact group is faulty. Sometimes the problem lies not in the block itself, but in the oxidation of the contacts in the connector. Try cleaning them with a special spray or cleaning the contacts by hand, but this must be done very carefully so as not to damage the fragile plastic.
⚠️ Attention: When checking the voltage under load (when the starter is turning), make sure that the multimeter probes are securely fastened. Accidentally shorting the test leads may damage the fuses or the engine control unit.
It is also worth paying attention to the condition of the fuses responsible for the ignition system. Although they protect the circuit, their combustion is often a consequence rather than a cause. If you replace a blown fuse, and a day later it burns out again, the problem is definitely in the contacts closing inside ignition switch.
- The car doesn't start the first time
- Stalls immediately after starting
- No power to dashboard
- Sparks and burning smell
Preparation for replacement and necessary tools
To successfully replace the contact group, you will need a standard set of tools and several specific devices. You don't need to be a professional auto mechanic, but accuracy and attention are key. Electrical work requires caution, especially when you're dealing with under-dash wiring.
List of required tools:
- 🔧 A set of screwdrivers (phillips and flat) for removing the plastic of the steering column
- 🔨 Hammer and chisel (or drift) for knocking out the fixation pin
- 🔋 Multimeter to check for voltage
- 🛠 Pliers and wire cutters
- 🧤 Protective gloves and glasses for eye safety
Don't forget to purchase a new contact group. For Nissan Almera Classic There are both original parts and high-quality analogues. The original block is more expensive, but its resource is higher. When purchasing, be sure to compare the markings on the old unit with the new one to make sure the connectors and pin locations are compatible.
☑️ Preparation for replacement
Step-by-step replacement instructions
Start by disconnecting the battery. This is a mandatory safety rule for any manipulation of the car’s electrical system. Remove the negative terminal and set it aside so you don't accidentally short out the circuit while working on the wiring. Let the car sit for a couple of minutes to relieve any residual voltage in the systems.
Next, you need to remove the lower and upper steering column covers. They are attached with several screws and latches. Be careful, plastic can be brittle, especially on cars more than 10 years old. Unscrew all the screws and carefully unclip the fasteners, being careful not to break the fasteners.
When access to the lock is open, you will see the cylinder itself and the contact block screwed to it. Disconnect the electrical connector. To do this, press the connector latch and pull it towards you. After this, you need to unscrew the bolts securing the contact group to the lock body. Usually there are two or three of them, depending on the modification.
The most difficult step is removing the pin that secures the lock cylinder in the case. It is located on the side, in a special recess. You need to turn the key to the "ACC" (accessories) position to move the mechanism and then carefully drive the pin out. Use a thin drill or drift and a hammer. Do not use excessive force to avoid damaging the housing.
How to knock out a pin correctly?
You need to gently tap the pin until it comes out of the housing. If it is stuck, you can lightly lubricate the entry point with penetrating lubricant, but do not use oil as it may stain the contacts of the new part.
After removing the old unit, install the new one. Make sure the contact positions match. Insert the new block into place and secure with bolts. Return the pin to its place, making sure it fits snugly in the hole. Connect the electrical connector until it clicks.
Before assembling the plastic casings, check the operation of the lock with the battery connected. Insert the key and check all positions: ACC, ON, START. Make sure the starter turns and the light goes out when the key is released.
Important nuances and common mistakes
One of the most common mistakes when replacing is incorrect connection of wires. Some vehicles may have different wire colors than standard, so always refer to the wiring diagram. Don't rely solely on the color of the insulation, as the previous owner may have changed the wiring. Use a multimeter to test each wire before final assembly.
Lubricating the mechanism is also often forgotten. If you removed the lock cylinder, it must be lubricated with a special lock lubricant. Use graphite or silicone lubricant, but never lithol or grease. These substances can attract dust and over time clog the mechanism, making the key difficult to turn.
Pay attention to the condition of the wires going to the connector. If they are melted or show signs of overheating, they must be replaced. Poor contact in the wire can cause the new contact group to quickly fail due to overheating. If the connector melts, it is necessary to unsolder the old wires and solder new ones using heat shrink tubing for insulation.
| Key position | Assigning contacts | Connected consumers |
|---|---|---|
| LOCK (0) | All circuits are open | No consumers |
| ACC (1) | Accessory chain | Radio, cigarette lighter, power windows |
| ON (2) | Main ignition | Dashboard, ECU, fuel pump, generator |
| START (3) | Starting circuit | Starter, ignition relay |
Correct diagnosis and replacement of the contact group requires attention to detail. An error in the connection may result in a failure of the starting system or a short circuit.
Repair cost and completion time
Replacing the contact group is a procedure that takes from 1 to 2 hours if you have the necessary tools and experience. If you decide to contact the service, the cost of the work will be approximately 1500-2500 rubles, depending on the region and level of service. This is significantly cheaper than replacing the entire lock assembly if the problem is only in the electrical part.
The cost of the part itself varies. Original from Nissan will cost 3000-5000 rubles. High-quality analogues (for example, brands from Turkey or China) cost in the range of 1500-2500 rubles. When choosing, it is worth considering that cheap analogues may have lower quality contacts that quickly oxidize.
If you decide to do the repairs yourself, your savings will be the full cost of the service plus time. The main thing is not to rush and follow safety precautions. Improper assembly may cause the steering wheel to lock in motion, which is a critical situation.
⚠️ Attention: Never leave the steering column disassembled without securely fixing the steering wheel. If the steering wheel turns at an unpredictable moment, this can lead to loss of control of the car, even when parked.
After completing all the work, be sure to check the operation of all systems: lights, power windows, radio and engine starting. Make sure the key turns smoothly in all positions and returns to its original position without binding.
FAQ: Frequently asked questions
Is it possible to replace only the contacts and not the entire unit?
Theoretically it is possible, but in practice it is very difficult and unreliable. The contacts are often soldered to the board or pressed into the case. It is better to replace the entire unit to avoid oxidation problems in the future.
Why does the new lock get hot during operation?
Heat may indicate poor connector contact or an overloaded circuit. Check for oxidized wires and make sure the starter is not drawing excess current due to a fault.
What should I do if the pin breaks during removal?
You will have to drill out the remaining pin and insert a new one. If the locking mechanism is broken, the entire ignition switch assembly may need to be replaced, as it will be extremely difficult to repair.
Is it possible to start the car if the contact group does not work?
In an emergency, it is possible to short the starter wires directly, but this is not safe and is not recommended for regular use. It is better to immediately replace the faulty part.
How often should the ignition switch be lubricated?
It is recommended to lubricate every 2-3 years or when jamming occurs. Use only special lubricants for locks, avoiding oils and thick compounds.