Vehicle anti-theft alarm and common troubleshooting

　　Car anti-theft devices developed from the initial mechanical control to electronic passwords, remote control calls for help, and information alarms. Early anti-theft devices were mainly used to control interlocking mechanisms such as door locks, doors and windows, starters, brakes, and cut off fuel supply, and to prevent thieves. Special socket wrench designed for disassembling parts.With the development of science and technology, automobile anti-theft devices are becoming more and more rigorous and perfect, mainly for the protection of the entire vehicle, and constantly launching new products.

Three anti-theft types of vehicle anti-theft alarms

Vehicle anti-theft alarms can be roughly divided into mechanical anti-theft locks, electronic anti-theft devices and GPRS network positioning anti-theft alarms

XNUMX. Mechanical anti-theft lock

The purpose of anti-theft is achieved mainly by locking the steering wheel and tires. This kind of anti-theft lock only prevents theft and does not alarm, and the anti-theft performance is not thorough.Because of its feature of preventing but not reporting, it is often easy to be damaged by master unlockers, and it is troublesome to disassemble and assemble.Its advantage is that the price is cheap and generally ranges from tens or hundreds of dollars.

The choice of mechanical anti-theft lock is mainly judged by the material of the lock body and the structure of the lock core.

XNUMX. Electronic anti-theft alarm

Vehicle electronic anti-theft alarms mainly rely on locking the ignition or starting, and vibration sensor alarms to achieve the purpose of anti-theft.It also has anti-theft and sound alarm functions.Electronic anti-theft alarms are mainly controlled by remote control. The current electronic anti-theft devices on the market are mainly divided into one-way remote control and two-way interactive remote control. One-way remote control anti-theft alarms are equipped with vibration detection door control protection and microwave or infrared probe functions. In addition, many convenient and practical additional functions have been added, such as: remote central control door lock, remote control of heating and cooling air, remote control of electric doors and windows, and remote opening of the luggage compartment.The two-way electronic anti-theft device has all the functions of a one-way anti-theft device. In addition, within a certain distance, not only can the vehicle be remotely controlled by the owner, but the vehicle can also transmit its own status to the owner through the LCD display on the remote control. For example, which side of the car door is opened or the window glass is broken.

but.The installation of the electronic anti-theft alarm is more complicated, and the vehicle circuit needs to be disassembled and assembled, which is likely to cause damage to the vehicle circuit.Due to the use of infrared and microwave control, the effective distance between control and alarm is short; many car thieves use wireless signal detectors to detect vehicle control signals and then simulate and crack the anti-theft system.

The main advantage of the vehicle electronic anti-theft alarm is its anti-theft alarm capability, which can serve as a reminder to the owner within a certain distance.

XNUMX. GPRS network positioning anti-theft alarm

The vehicle GPRS network positioning anti-theft alarm uses the most advanced global positioning system to track the vehicle 24 hours a day. When the vehicle position moves, it will immediately send an alarm signal to the vehicle owner’s mobile phone to remind the vehicle owner.The location alarm also has the function of checking the location of the vehicle, driving track and emergency alarm at any time. Your family can check your location at any time. You can also make an emergency alarm when you encounter robbery and other dangers.Due to the GSM telephone alarm, the alarm signal is stable and not limited by distance.These features are unmatched by traditional mechanical anti-theft locks and electronic anti-theft systems.

Common troubleshooting of vehicle anti-theft alarm

The use of car anti-theft alarm system is realized with the help of car power supply and some circuits of the car itself. Once the anti-theft device fails, it will affect the normal use of the vehicle.This article analyzes the causes of some common failures and introduces the treatment methods, most of which can be handled by the user by referring to the solution.

Example 1. Fault phenomenon: The remote control operation does not work. When pressing the function buttons of the remote control, the red LED indicator of the remote control does not light up.

Reason analysis: This fault is mostly in the remote control itself, and there are the following situations: (1) the battery is exhausted; (2) the positive and negative reeds of the battery are rusty or have poor contact; (3) the remote is exposed to rain or Water, oil immersion, etc.In this regard, the circuit board can be taken out, cleaned with industrial alcohol, dried with a household electric hair dryer or after it is naturally dried, it can be used.

Example 2. Fault phenomenon: The remote control distance is getting shorter and shorter, and the LED brightness of the remote control becomes dim or flickers when the signal is transmitted.

Reason analysis: This phenomenon is mostly due to insufficient battery power, just replace the battery.In addition, it is recommended not to adjust or replace the components of the remote control yourself to avoid greater losses.

Example 3. Fault phenomenon: a function key of the remote control fails, and the LED indicator does not light up when the key is pressed.

Reason analysis: a function key is invalid (other function keys are normal) mostly because the function key is damaged or the solder joints between the key pins and the circuit board are disconnected.The buttons of the remote control are mostly micro-switches, so you should use light force during normal use, and pay attention to waterproof, drop-proof and heavy pressure.

Example 4. Trouble phenomenon: When the remote control is not used, the LED indicator often lights up by itself, or as long as the battery is installed, the LED indicator is always on, and there is no response when operating the remote control.

Reason analysis: the indicator light often lights up when the remote control does not press the button, usually because the remote control button is mechanically damaged.The button feels bad and has no elasticity, just replace the button.For the code-hopping remote control, there is no response when pressing the function keys of the remote control. After replacing the battery or reinstalling the battery, the LED indicator lights up for 20-40 seconds, and then there is no response.This means that the keys are short-circuit damaged. If the hand feels no abnormality, you can test the keys on the road with a multimeter R×1, and then replace the short-circuited keys.

Example 5. Failure phenomenon: The vehicle will automatically turn off and enter the alarm state after driving for about 30 to 40 seconds. After the anti-theft function is released, the above situation is repeated during driving, and so on.

Reason analysis: This phenomenon is caused by operating the remote control in the car, which causes the second automatic anti-theft. As long as the door is opened and closed again after pressing the anti-theft function key, the problem can be solved.The remote control for automobile anti-theft system is limited by volume. Generally, there are no more than four function keys. In this way, each key is often assigned several functions. In a certain state, the function controlled by the same function key is different, or a certain function is composed of multiple functions. The two buttons are coordinated to complete, so special attention should be paid when using them.

Example 6. Trouble phenomenon: The vehicle is in the anti-theft state, use the remote control to release the anti-theft failure.

Reason analysis: In the anti-theft system, due to the failure of the remote control or the system main unit (mostly the main unit is the remote control receiving circuit failure), the anti-theft failure is cancelled (the remote control loses control of the system), and the car direction light (double jump light) flashes , The alarm horn often buzzes, and the vehicle cannot start driving.At this time, the anti-theft system can only be temporarily removed, which requires the user to pay attention to the general installation position of the anti-theft system host.If you don’t know the location of the anti-theft device, you can find the system host according to the anti-theft system’s LED indicator light, ultrasonic sensor probe or alarm horn and other components, and unplug the connector that connects the anti-theft system host to the vehicle.In addition, some remote control car anti-theft alarm system mainframes are equipped with an emergency release function, and the use of the anti-theft device can be suspended without dismantling the system mainframe.

Example 7. Trouble phenomenon: The car anti-theft system is working normally, the ignition motor is running normally, but the vehicle cannot be started.

Cause analysis: This phenomenon may be caused by the alarm or the car’s own electrical failure.The judgment method is: cut off the two thick wires of the ignition relay (12V/30A, usually placed near the car key door) of the car anti-theft device accessory. If the vehicle can start at this time, it means that the anti-theft system is faulty, and most of them are relays. damage.If the vehicle still cannot start after short-circuiting and cutting off the two thick wires of the ignition relay, it means that the vehicle’s own circuit is faulty.In addition, when the vehicle encounters a bumpy road during driving, it is easy to extinguish or instantaneously extinguish. Special attention should be paid to whether the normally closed contact of the cut-off ignition relay has poor contact and loose wiring.

Example 8. Trouble phenomenon: When turning on one side of the car, the other side also lights up.

Reason analysis: This fault is the breakdown of the diode of the anti-theft system to control the voltage output of the car’s direction light (double jump light) (in some models, the two diodes are inside the host, and some are attached to the connection). Replace the diode of the same model to eliminate Fault.

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