Many car owners are familiar with the situation: you arrive, for example, at a supermarket, park your car and set the alarm. You come back with a bunch of packages, press the button on the key fob - and the car is like someone else’s, it doesn’t even think about answering. As a result, you open it with the key, the siren goes off, and you already remind yourself of a burglar. What to do when the alarm does not respond to the key fob? Let's figure it out.
Alarm does not respond
The battery in the key fob is dead
The first and most likely reason is if the car alarm does not work. The batteries may have run out or moved from their normal place. Think about the last time you changed them. A dimming screen or LED may indicate dead batteries.
To remedy the situation, remove the battery from the case and lightly tap it on another hard object. This may be enough to disarm the car. In general, it’s a good idea to always carry a spare battery with you.
You are in an area of radio interference
Radio waves are often jammed near sensitive enterprises, closed facilities, and airports. This could be a powerful electromagnetic field from some object. Interference can be caused by large concentrations of cars, such as in the parking lots of shopping centers, as well as by cash-in-transit vehicles (so avoid stopping next to them).
Try bringing the alarm key fob close to the place where the system receiver is installed and press the button. If this does not help, you can tow the car 200-300m from this area and try to open it there.
There are not enough conditions for wave transmission
It is possible that there is not enough operating voltage on the dead car battery to disarm the system. Also, in particularly severe frost, the key fob may slow down.
Some transmitters are damaged by repeated button presses outside the signal coverage area (for example, when the buttons are pressed in a trouser pocket or children play with a key fob).
Wear and tear of the security system
Over time, the radius of the key fob may decrease. The transmitter receiving antenna installed in the car may be faulty or errors were made when installing the alarm system.
The synchronization of the remote control with the car is broken
This means that the key fob has lost contact with the unit and needs to be reprogrammed. We open the car, and since it is not removed from the alarm system, we use the emergency shutdown function. Next, to program the transmitter, refer to the manual of your alarm system. Each manufacturer has its own characteristics, but in general the algorithm is not complicated and runs quickly.
The car is not disarmed
System problems with the control unit
If the system does not show any signs of life, this may be due to the fact that the software has disappeared from the main unit. As a rule, it needs to be re-flashed. This is done by service companies that install alarms.
Electronics technical failure
The most unpleasant news is the failure of the central alarm unit. They cannot be repaired, they can only be replaced. This happens infrequently and leads to replacement of the entire system, which can be expensive.
How to understand that your alarm unit is “dying”:
- Previously working functions are missing
- the system responds inadequately or does not respond at all to key fob commands
- spontaneous activation of the siren.
Engine blocked
Occasionally, the engine lock relay may fail. If this is the reason, the car simply will not start. Knowing where the relay is located and having experience in car repairs, you can disable the blocking yourself by bridging the correct contacts in order to get to the specialists on your own. But if you are not confident in your skills, do not take such actions under any circumstances, this can lead to serious damage to the car, as well as short circuits and fire.
Alarm goes off frequently
Negative influence of the environment on electronics
Contacts and relays often fail. Most often it gets to the hood limit switches. Limit switches are buttons that are pressed by the hood when closing so that the alarm remembers the open/closed position. Since these contacts are in an aggressive environment, they often become clogged with dirt, moisture gets in, they oxidize and rust. As a result, they do not work correctly, and may even react to the opening of the hood. The problem can be fixed by replacing the limit switch.
Sensors that need maintenance
Firstly, during installation the shock sensor could be configured to be more sensitive. The siren can even be triggered by gusts of wind. Exit – change sensitivity parameters.
Secondly, quite often external tilt sensors, shock sensors, and a microwave volume sensor fail. This fault is considered a “floating” fault, since they are scattered throughout the car, and it is difficult to determine the cause of the breakdown. In any case, it would be better to contact the service.
The alarm does not open or close the doors
The car is safely armed, but when you open it, the key fob lights up “open”, but the central locking is locked? Listen to see if the central locking works. If yes, then first of all we check the fuses, the so-called “brains”.
Tomahawk does not open doors: what to do
Let's look at one more case. The Tomahawk alarm unlocks but does not respond to the passenger door. What are the reasons and how to remove the blocking?
- The connection between the driver's door and the alarm control unit is broken. Most often, a break occurs at the junction of the wiring from the driver's door to the car interior. Remove the corrugation. Inspect the wires. Repair it.
- Lock drive malfunction. Move closer to the car. Press the open key. Listen, you should hear the click of the lock drive. If there is no click, then the drive is faulty. You can change the lock mechanism yourself. Be careful with levers, rods and plastic tips. But first you need to remove the lock from the car. Insert the key into the door lock and open it. If the alarm reacts (the siren and lights work), then immediately press the service button.
Car battery is dead
Many people ask the question: why doesn’t the car unlock with the key fob alarm? Of course, it is impossible to give a definite answer, but in fact there can be many reasons. An equally common problem is a dead battery. If you find yourself in such a situation, then get as close as possible to your iron friend and press the button one more time. Very often, carrying out such a manipulation helps to open the car, but there is a very small chance that you will be able to drive it away. After all, the battery is completely discharged.
How to disable automatic door closing
To remove spontaneous latching of the central locking system of the anti-theft complex Tomahawk Q9, Z3, 434 mhz frequency, D 900, CL 500, 9.9, 9.7, 10.1, 7.1, 9.3 during automatic arming, follow the steps.
- Activate the ignition.
- Press the Override key six times.
- Turn off the ignition.
- Six siren sounds will sound. Confirming entry into setup mode.
- Click the Override key five times.
- Press the "Lock/zZ" button. The machine's automatic closing function is disabled.
The alarm won't let you start the car.
Your vehicle is equipped with Tomahawk TZ 9010, TW 9020, 7010, 9030, 9031, 4000, 9100, 9000, 9011, 5000. You try to start the car, but it won’t start. What's the matter?
- The engine lock mode was accidentally activated. Study the icons on the remote control. Disable the feature.
- Inspect the alarm control unit for blown fuses. Replace them. Try starting the car.
- Check the door, trunk, and hood limit switches. Incorrect operation of one of them will block the engine from starting.
- Insufficient battery charge. Measure the battery voltage. Charge it or replace it with a new one.
The technical error
The car may not be deactivated due to serious technical reasons, which can only be resolved by a specialized service center. It can be:
- problems with the alarm control unit itself, associated with the disappearance of software from the main unit. It will need to be taken to an alarm installer for reprogramming;
- failure of the main alarm control unit leads to the need to change the entire system completely. You can determine that the main unit stops functioning by the following signs: the siren turns on spontaneously, the alarm system does not respond correctly to commands from the key fob, not all functions work. This is the most expensive problem; it can only be solved by completely replacing the old security system with a new one;
- The car may not respond to the alarm when the engine relay is blocked. To eliminate the malfunction and unlock it, you should contact service specialists.
- problems in the peripheral devices of the security system. There is no contact in the door and hood switches. Contacts in these parts of the car are susceptible to frequent environmental influences - humidity, pollution. The problem is solved by purchasing new ones and replacing them. Some motorists clean the limit switch contacts.
If you have additional central locking installed
Cars that do not have a central locking system supplied from the factory are equipped with electric drives. They are controlled by power relays of the security system Tomahawk 9.5, 7.2, CL 550, LR 950 LE, G 9000, S 700, Z1. Reasons for failure:
- The car doors do not close, they open normally. The locking relay has failed. The alarm control unit requires repair;
- The car won't open or close. Check whether the control unit accepts commands from the key fob by pressing other keys. If the signals are not perceived, then re-register the remote control;
- The pager cannot be reprogrammed. Antenna module failure;
- if the commands are perceived normally, check the integrity of the fuses, the presence of power to the relay, and the absence of breaks in the electrical circuit.
Radio interference problems
If the car does not open with the Starline alarm key fob, then the problem may be hidden in radio interference. Sometimes the signal from your remote control may be jammed. This happens very often, especially if you are in a difficult to reach area. In this case, it will be quite difficult to open the car. For example, radio waves will weaken significantly if you are near facilities such as an airport, military base, or other important government installations. To check for radio wave interference, look at your cell phone.
In order to still open your car, bring the remote control as close as possible to the signal receiver and press the button one more time.
Standard central locking
With the original security system installed, it often occurs that the key fob emits a signal, but the doors do not open or close. What are the reasons?
- Check for ground on the alarm control unit when arming the vehicle. If it is missing, inspect the location where the Tomahawk is connected to the standard wiring. Possibly poor contact or oxidation.
- On some car models (Renault Logan, Koleos), the standard lock does not lock until the control unit receives information that all doors are closed. Trunk and hood. The lock drive operates twice: closing and immediately opening. Check the tightness of the doors closing, the serviceability of the door switches and the wires going to them.
Defective twists
One of the common reasons for the incorrect operation of the anti-theft system is poor quality of twists.
- Strip insulation and oxidized wires. Twist them again and solder them using rosin.
- One of the reasons for strand breakage is the short length of the moving strands. The wires are very stretched when the door is opened. Pull out the tourniquet completely. Extend the wires by soldering the joints. Insulate twists.
Car alarms connected via CAN bus
If the operation of the central lock connected to the CAN bus malfunctions, it is necessary to reprogram it.
- Disarm the car.
- Remove the Tomahawk control unit for easy access to the CAN module setup button.
- Disconnect power from the control unit for thirty seconds. Connect the power connector.
- Press the programming button until the LED indicator starts blinking.
- Release the key. Count the number of LED lights equal to the first digit of the CAN program number.
- Press the programming button until the LED flashes.
- Use the method described above to enter the values of the second and third digits of the code.
- After you enter the third number of the password, you will automatically exit the programming mode. Ten LED flashes will follow.
What to do if the alarm stops responding to the key fob
If the car does not open with the key fob alarm (the reasons for this phenomenon are described in this article), then in this case you can perform two specific actions to disable it:
- Use the emergency shutdown feature. Do not forget that each alarm system has its own code, which the driver must remember during its installation. To enter it, find the Valet button in your car. It is responsible for the operation of the system itself and performs many functions. Typically, such a button can be found inside the car itself (for example, under the steering wheel or near the fuse box). Only after you find this button can you enter the secret code.
- Another way to turn off the alarm is to bring the key fob as close as possible to the control unit itself and very often press the car open button on the remote control. Most often, such fraud is enough to disable the car alarm. This almost always helps to transmit a wave that is quite acceptable for switching off.
Tomahawk remote control repair
The reason for the alarm not closing the doors may be a simple breakdown of the corresponding key. The repair is simple and the button is easy to find. Tools and accessories:
- thin figured screwdriver;
- solder with flux;
- tweezers;
- button to replace the broken one.
- Disassemble the key fob body using a screwdriver.
- Once disconnected, remove the boards.
- Unsolder the old key.
- Install a new key and solder it. Avoid overheating the button.
- Reassemble the key fob in reverse order and check its operation.
The reason is in the Tomahawk central unit
Often problems in closing and opening a car lie in the alarm control unit Tomahawk 7100, LR 1010 LC, X5, 868 mhz, SL 950, Z5, CL 700, X3. The operation of the central locking is controlled by two relays. Finding them will not be difficult; just trace the tracks from the corresponding connector. Reasons for failure:
- Relay contacts are welded. Replace the relay with a new one;
- there is no control signal to the relay. The winding driver has failed. Install a new one.
If you cannot identify the cause of the malfunction yourself and make repairs, you should contact a service center.
The following malfunctions are possible:
- the relay contacts are welded (constantly closed regardless of commands) or burnt out (normally closed and normally open contacts are constantly broken from the common contact);
- the control signal does not arrive at the relay winding (the power driver of the windings is faulty - the nearby ULN2003A transistor assembly is located).
To check, you need to connect the alarm board to the wiring and use an LED probe to check whether a negative polarity pulse is applied to the relay winding when the command from the key fob is activated. Next, either the driver is replaced (if the signal is not received) or the relay itself.
Miniature printed circuit relays used in alarms have standard sizes and pinouts; finding an analogue will not be a problem.
When is the antenna at fault?
The feedback alarm system is equipped with an external radio module, which is connected to the central unit by a loop. Inspect parts for damage or poor connections.
Remove the module from the windshield. Disassemble the body. There is a printed circuit board inside. Find a capacitor on the board, which is a filter for the power supply circuit. Inspect the tracks from the capacitor to the electrical connector. Check the voltage on the capacitor legs.
The cause of the malfunction may also be corrosion of the antenna connection point. Make repairs.
- Melt and remove oxidized solder.
- Clean the track from the antenna pad.
- Solder the antenna to the track.
- Fill the soldering area with hot glue.
For inexpensive alarm systems, the situation when pressing the key fob buttons does not produce any result is common. Mainly due to the fact that they use the old element base to reduce the cost, and different manufacturers have the same type. Due to the use of broadband transceivers, such alarms are sensitive to the level of interference - where modern narrowband high-end alarm transceivers work without problems, inexpensive car alarms lose stable communication.
Let’s not forget about the elementary reasons why the alarm system does not see the key fob (the key fob is broken, the contacts on the central unit have oxidized), and so on. Therefore, it is worth remembering what to do if the Tomahawk alarm does not respond to commands from the key fob.
Sensors are not working correctly
Today, modern cars have a huge number of sensors installed. So, the alarm system is perfectly oriented towards their readings. For example, if the shock sensor is particularly sensitive, then the alarm will go off on its own even from ordinary wind or a car passing quickly. In this case, you need to correctly adjust all the sensors, and such situations will not arise.
Experts recommend that if you have any problems with the alarm system, contact a service center, because a car is not the cheapest pleasure, so take care of it and operate it correctly. By determining the cause of the breakdown in advance, you can protect your iron friend from break-ins.
Tomahawk Quick Shutdown
If you need to go urgently (and according to the “law of meanness,” this usually happens), then it is better to use the emergency alarm shutdown procedure. On Tomahawks, the Valet button is used for this (here called Override according to the instructions). Moreover, in most Tomahawk models, to protect the machine, emergency shutdown is performed using a PIN code, but there is an exception in the form of Tomahawk 10.1. Whether the PIN code is activated in the system can be seen on the screen of the main key fob: there is an indicator of the same name.
To emergency disable the alarm without a PIN code, open the door with the key, then turn on the ignition as quickly as possible and press the Override button 3 or 4 times (depending on the model - we have already written about this earlier). After this, the ignition is turned off and the alarm goes out of security mode.
Possible problems with the key fob
Most often, the car does not open with the key fob alarm precisely because of problems with the small remote control itself. There is a very high probability that the batteries may have run out. Therefore, replace them first.
Now carefully inspect the keychain itself. If this device is equipped with a screen, then pay attention to whether it lights up after you press the corresponding button. If there is no screen, then look for a diode, which very often car owners install themselves, signaling a low battery charge.
If you need to open the car urgently, and there are no spare batteries in your pocket, do not be discouraged and try to follow a certain procedure. Remove the old batteries from the remote control and knock them together several times. Now return the batteries to their original place and try opening the car again.
It is possible that the car does not open with the key fob alarm due to a breakdown of the remote control itself. In this case, the problem lies in a special sensor. This can occur as a result of pressing the car unlock button very often (for example, accidental presses in your pocket). If you have a spare remote control, use it to open the car.