Diagnostic Code Encounter 1720 on the car's on-board computer Nissan often causes panic among drivers, since this signal is directly related to a critical safety system. In most cases, this error indicates a malfunction in the sensor control circuit ABS or a problem with the brake system module, which can lead to failure of the anti-lock braking system during emergency braking.
Ignoring this warning is strictly not recommended, since even if the main brakes continue to work, the absence of anti-lock significantly increases the risk of skidding on slippery roads. For model owners Qashqai, X-Trail or Almera Understanding the nature of this error is the first step to safe operation of the vehicle.
In this article we will examine in detail the technical aspects of the origin of the code. 1720, we will consider the most common causes of its occurrence and provide a step-by-step algorithm of actions for self-diagnosis. It is important to understand that in some situations the problem lies not in the mechanics, but in the electrical wiring or software failure of the control unit.
The essence of error 1720 and the operation of the ABS system
Code 1720 in the ecosystem Nissan usually indicates a loss of communication with one of the wheel speed sensors or an incorrect signal entering the brake control unit. System ABS continuously monitors the speed of each wheel, and if data from one of them is missing or contradicts the physical parameters of the vehicle’s movement, the controller records a failure.
In modern cars Nissansuch as Murano or Patrol, ABS system integrated with stabilization system VDC and a braking assistance system. Therefore, error 1720 is often accompanied by the lighting of several lamps on the dashboard at once: the ABS indicator, the VDC OFF icon and a warning about a brake system malfunction.
If this error occurs, the control module ABS goes into emergency mode, disabling the anti-lock functions. This means that if you press the brake pedal too hard, the wheels may lock, resulting in loss of control. The driver must be prepared for the fact that the car's behavior in difficult road conditions will change.
The main reasons for the appearance of a fault code
Reasons for the error 1720 can range from trivial contamination of the sensor to serious damage to the electronic unit. The most common problem is failure wheel speed sensor, which over time loses its magnetic properties or is damaged mechanically.
The second most popular reason is a violation of the integrity of the wiring. Vibrations, temperature changes and exposure to road chemicals can lead to oxidation of contacts or breakage of wires going to the sensors. Particularly vulnerable are the connection points of the harnesses in the engine compartment and in the wheel arches.
Sometimes the problem lies in the brake control module itself. The internal components of the board may burn out due to voltage surges in the on-board network. It is also worth noting that on some models, for example Nissan Teana, the error may occur due to a malfunction of the sensor rotor (ring gear), which may be dirty or damaged.
Often the cause of failure is low voltage in the battery. If battery is discharged or the generator produces unstable current, the control unit may incorrectly read data from the sensors, which is interpreted by the system as error 1720.
- ❌ ABS sensor damage due to gravel impacts or housing corrosion.
- ❌ Open or short circuit in the wiring harnesses connecting the sensors to the unit.
- ❌ Contamination or damage toothed ring (rotor) on the wheel hub.
- ❌ Control unit malfunction ABS/VDC, requiring replacement or flashing.
Diagnostics and testing of system components
To accurately determine the cause of the error, it is necessary to conduct a comprehensive diagnosis, starting with a visual inspection and ending with measurements with a multimeter. The first step is to check the condition of the wheel sensors. They are located in the wheel hubs and are protected from external influences, but over time they can fail.
Remove the wheel and carefully inspect the speed sensor. Make sure that there are no chips, cracks or signs of heavy contamination with metal shavings. Often it is enough to simply clean the sensor from dirt and check the reliability of the detachable connection.
Next, you need to check the integrity of the wiring. Use a multimeter to test the continuity from the sensor to the ABS control unit connector. Pay attention to the areas where the wires pass through the moving elements of the suspension, as this is where insulation chafing most often occurs.
An important step is to check the ring gear on the hub. It should be clean and have an even distribution of teeth. If the ring is chipped, rusted, or has dirt stuck to it, it can distort the signal to the sensor, causing a 1720 error.
⚠️ Attention: When checking the wiring, be sure to disconnect the battery to avoid short circuits and damage to the electronic control unit. Working with electrical equipment requires compliance with safety precautions.
If a visual check does not reveal any problems, you should proceed to measuring the resistance of the sensors. For most models Nissan the normal resistance value is in the range from 1000 to 2500 Ohms, however, it is better to check the exact parameters in the technical documentation of a specific car modification.
It is also worth checking the condition of the connectors on the ABS unit itself. Oxidation of the contacts inside the connector can prevent data transfer. In some cases, simply cleaning the contacts with contact cleaner spray and applying a conductive lubricant helps.
- ABS light came on
- Brakes work fine
- Lost control while turning
- The engine stalls
Stages of repair and replacement of faulty components
Once the cause has been identified, repairs must begin. If the problem is the speed sensor, replacing it is the easiest solution. The replacement process varies depending on the car model, but the general principle remains similar.
First remove the wheel and the guard, if installed. Unscrew the sensor mounting bolt and carefully remove it from its seat. Be extremely careful not to damage the sensor and wiring.
Install the new sensor within the recommended clearance (if adjustable) and securely fasten it. Connect the connector and make sure it clicks into place. The remaining dismantling and installation work is carried out in the reverse order.
If the problem lies in the wiring, it is necessary to restore the integrity of the wires. Use special heat-shrink tubing and high-quality electrical tape to insulate the twists. Ideally, you should replace the entire damaged section of wire to avoid future failures.
- 🛠️ Replacing the sensor requires care when removing the old element so as not to break its fragile body.
- 🛠️ Wiring repair must be done using a soldering iron and quality materials for reliable contact.
- 🛠️ Replacing the ABS block - an expensive procedure, often requiring adaptation and coding of a new module.
☑️ Instructions for replacing the sensor
In some cases, when replacing the sensor and repairing the wiring do not help, it may be necessary to replace the entire ABS module. This is a complex procedure that often requires the connection of specialized equipment to adapt the new unit to the vehicle system.
It is important to note that on all-wheel drive vehicles such as Nissan X-Trail or Qashqai, the ABS system is closely related to the torque vectoring system. Therefore, any work on the brake system must be carried out with special care.
What should I do if error 1720 returns after a reset?
If the error returns immediately after reset, this indicates a permanent problem. In this case, it is necessary to repeat the diagnosis, paying special attention to the wiring and contacts. Perhaps the problem is hidden in the control unit or in the sensor itself, which gives incorrect readings even if it appears to be in good working order.
Resetting the error and testing the system
After performing repair work, it is necessary to reset error code 1720 from the control unit memory. This can be done using a diagnostic scan tool connected to the OBD-II connector, or by disconnecting the battery for a few minutes, although the second method is less reliable.
For a quality reset, use professional equipment or a high-quality multi-brand scanner. Connect the device to the connector, select the car model and go to the ABS system diagnostic menu. Find the option "Erase error codes" and confirm the action.
After the reset, a test movement must be carried out. Accelerate to a speed of 10-15 km/h and brake sharply several times to activate the ABS system and check the operation of the sensors. If the dashboard lights go out and do not come back on, the problem has been resolved.
It is important to ensure that the VDC system is also working correctly. If you have diagnostic equipment, you can carry out a full cycle of testing of all vehicle safety systems to eliminate hidden faults.
If error 1720 appears again after several driving cycles, this may indicate a hidden problem that was not detected during the initial diagnosis. In this case, it is recommended to contact a specialized service for an in-depth analysis.
After resetting the error, be sure to go through a test route of at least 5 kilometers, including various braking modes, so that the system fully adapts to the new operating conditions.
Table of common problems and solutions
For the convenience of analyzing the situation, below is a table summarizing the most typical reasons for the appearance of code 1720 and how to eliminate them on various models Nissan.
| Symptom/Cause | Possible breakdown | Remedy |
|---|---|---|
| ABS light stays on constantly | Speed sensor malfunction | Replacing the sensor on a new wheel |
| Error appears when turning | Damage to the ring gear | Cleaning or replacing the hub |
| Indicator flashing when braking | Broken wiring | Finding and repairing a broken wire |
| Simultaneous ignition of ABS and VDC | Control unit failure | Checking power supply and replacing the module |
| Error 1720 when cold | Problem with connector pins | Cleaning and lubricating contacts |
Analysis of data from the table allows you to quickly navigate the problem and choose the optimal solution. However, remember that every vehicle is unique and an accurate diagnosis is always preferable to guesswork.
On models Nissan Note and March There are often problems with corrosion of sensor contacts due to the design features of the fender liners. In such cases, regular maintenance cleaning can prevent error 1720 from occurring.
Regularly checking the condition of ABS sensors and wiring is the best prevention of error 1720, allowing you to avoid costly repairs in the future.
Prevention and recommendations for use
To minimize the risk of an error occurring 1720, you must follow simple rules for operating the car. Wash the underbody and wheel arches regularly, especially in winter when reagents that accelerate corrosion are used.
When undergoing maintenance, be sure to ask mechanics to check the condition of the ABS sensors and the integrity of their wiring. This is a small thing that can save you significant money in the future.
Avoid extreme stress on the brake system if you know the sensors are in poor condition. Sudden braking on a slippery road can lead to a complete loss of control over the vehicle.
Monitor the condition of the battery. Low voltage can cause false activation of the ABS system and the appearance of code 1720. Regularly check the charge level and functionality of the generator.
- 🛡️ Regular washing suspension and wheel arches will protect the sensors from corrosion and dirt.
- 🛡️ Voltage control in the on-board network will help to avoid false alarms of electronics.
- 🛡️ Timely diagnosis at the first sign of problems with the brakes will prevent serious damage.
Remember that the ABS system is a complex electronic device that requires careful attention. Any interference in its operation must be carried out with an understanding of the principles of operation.
⚠️ Attention: Never try to reflash the ABS unit yourself without the appropriate equipment and experience, as this may lead to complete inoperability of the braking system.
If you are not confident in your abilities or do not have the necessary diagnostic equipment, it is better to entrust the repair to professionals. Road safety does not tolerate experimentation.
Following all recommendations and regular vehicle maintenance will help you avoid error 1720 and ensure the safe operation of your vehicle. Nissan in any road conditions.
Professional diagnostics and the use of original spare parts when repairing the ABS system guarantee the reliability and durability of the brake system.
Frequently asked questions (FAQ)
Is it possible to drive with error 1720?
Technically, the car continues to brake because the main hydraulic system is working. However, ABS and VDC are disabled, which makes driving unsafe, especially on slippery surfaces or when braking hard. It is recommended to correct the problem as soon as possible.
How much does it cost to replace an ABS sensor on a Nissan?
The cost depends on the car model and region. The original sensor usually costs from 2000 to 5000 rubles, and the work to replace it costs from 1000 to 3000 rubles. Non-original analogues may be cheaper, but their reliability is not always guaranteed.
Is it possible to reset error 1720 without a scanner?
In some cases, disconnecting the battery for 15-20 minutes helps, but this is a temporary measure. If the fault is physical (wire break or sensor failure), the error will return after the first start of the engine. For a reliable reset, it is better to use a diagnostic scanner.
Why does the error only appear when it is cold?
This may indicate the presence of a microcrack in the wire or oxidation of the contacts, which expand when heated and restore contact. The problem may also be in the sensor itself, which changes its characteristics when the temperature changes.
Does error 1720 affect fuel consumption?
Error 1720 does not have a direct effect on fuel consumption, since it only affects the brake system. However, if the VDC system begins to work incorrectly due to a malfunction in the ABS, this can indirectly affect the dynamics and driving style, which will ultimately affect fuel consumption.