The alarm has blocked the fuel pump, what should I do?

A good alarm system is a reliable protector against car theft. At the same time, we cannot talk about the car being 100% protected from theft and disassembly. Any alarm system, even a bank alarm, can be hacked. Another question is that this will take time. The better the alarm, the longer the time and complexity of hacking. Attackers involuntarily raise the question of the advisability of hacking a car with a good alarm system, if there is an option to choose a simpler “job”.

Like all electronic devices, car alarms can malfunction over time, or as it is now fashionable to say, “glitch.” At the same time, it either does not set the car alarm, or it goes off arbitrarily, or, even worse, it blocks the authorized (from the original key fob, tag or other programmed mode) disarming, and blocks the engine from starting. What to do in this case?

The alarm is blocking the fuel pump, how to turn it off

Engine start blocking is a function that is on the list of available options in almost any anti-theft system.
In this case, the system contains an immobilizer that identifies the owner by a special tag and allows the engine to start. Conventional car alarms that have a similar function in their arsenal can also block the engine from starting. According to experts who work with automotive electrical equipment, more than half of all cases of unexpected engine failures to start are directly related to car alarm malfunctions. Note that the complexity of implementing locks in this case is noticeably simpler compared to complex anti-theft solutions. This significantly increases the chances of removing the engine start lock yourself in the event of a breakdown or malfunction. Next, we will look at what the driver should do if the alarm blocks the engine from starting.

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Doesn't start with key fob

If your car does not start with the key fob, that is, the problem is related to the autostart of the car, then if you have a temperature sensor, you need to set it to a higher temperature. Then the car will be able to warm up automatically and there should be no problems with autostart. If the starline alarm also does not allow the car to autostart, then the problem may be related to the car’s wiring. It's worth finding out how the starter in your car is connected. If the starter connection occurs in a gap, then it is worth removing it and leaving one single wire.

It is possible that the car owner has reset the settings to factory settings. In this case, you shouldn’t even be surprised that your car won’t start from autostart. When such a problem occurs, the crawler stops working because your car's chip is not showing up, and that is why the car does not autostart properly. In order to solve this problem, you must definitely visit the service center where the alarm was installed. Re-setting the car alarm will take just a few minutes for the technicians and will save you from this problem.

It is also possible that the reason is in the car's wiring itself. Many inexperienced car enthusiasts do the car alarm connection themselves. It is worth looking at the connection of the lineman on your car and if it has many turns, then it is worth reducing the number and then perhaps this will be the solution to your problem.

Engine blocking with car alarm

If there are installed anti-theft systems, electrical equipment is responsible for blocking the engine start. Immobilizers or car alarms may be faulty and cause constant or occasional failures during operation.

It should be added that the severity of the problem will depend not on the specific model or brand of car, but on the complexity of the installed anti-theft security system.

Accidental activation of the engine lock function

First of all, carefully study the displayed icons on the alarm key fob. A common cause of blocking is accidental activation of additional functions. It is also necessary to monitor the readings of the LED indicator light (if equipped) in the vehicle interior, which serves as a light indicator of the alarm status. Flashing LED lamps in most cases indicate that the anti-theft function of the immobilizer is activated in the menu.

If, after turning the key in the lock and turning on the ignition, the warning lamp blinks frequently (for example, the StarLine car alarm) before starting the engine, and a pictogram with the inscription “immo” is displayed on the key fob itself:

One way to solve the problem is to remove the key from the lock, after which you just need to press the button to open the central door lock on the key fob.
You can also get out of the car, set the alarm to security mode, then disarm it and then start the engine.

In other words, you need to make sure that the alarm operates in the normal mode that is familiar to the owner. Up to 30% of cases of engine start blocking by alarms occur due to accidental changes in program settings. The driver’s task is to disable all unnecessary functions in the settings.

Using the StarLine alarm as an example, let us note that this system has the option of “two-stage” unlocking. Activation of the function may occur accidentally; a separate icon will light up on the key fob screen. To turn it off, you must hold down button 3 on the key fob. The key fob will emit two beeps, after which button 3 is pressed once again. Then button 1 is pressed for a few seconds, then the security functions are removed;

Why should you get rid of this option?

Therefore, the desire to get rid of the ill-fated option is completely justified. Of course, this does not apply to drivers who strictly follow everything written on paper and are afraid to interfere with the standard design of the car. But they too may simply be deceived by a system glitch.

Blocking scheme

Whatever anti-theft system is installed on the car, the electrical equipment is responsible for blocking the starter. This allows you to bring the search lens closer together, making it easier to find the area where modernization is needed.

As a rule, the complexity and severity of the problem mostly depends not on a specific anti-theft system or car model, but on the amount of functionality of the security system (set of protective elements).

As mentioned above, sensors can easily turn out to be faulty. They will periodically fail during operation.

You can determine a specific malfunction of the immobilizer sensor directly by the operation of the system. If an initially serviceable engine does not start, the engine does not respond to starting from the key fob or key in the ignition, then this is a clear sign of such a malfunction.

Disabling locks using the service button in the cabin

If there are no signs of unintentional activation of engine start interlocks, you can try to unlock the engine using the service mode. This mode is called Valet and is used to transfer the system to service mode. To activate, you need to insert the key into the ignition, turn on the ignition and then turn it off.

After this, you need to hold the service mode activation button for about 10-20 seconds. The result will be a notification using a special short signal, after which the signal lamp (indicator light, LED) will be constantly on. This method means disabling all security functions, which may also mean removing the engine locks. We add that after fixing the problem, it is necessary to activate the security functions of the alarm again.

Door locking when driving

Some owners of the Starline A91, A63 or A92 complex have a problem when the system does not close the doors when moving or, conversely, blocks them even without receiving the appropriate commands or reaching a certain speed. If the doors do not close, then you need to check the limit switches - perhaps they are faulty or the contact has come loose. Because of this, the central unit does not receive the command and cannot block.

If the doors are locked forcibly, without commands or high speed, then this is a programming error or a glitch in the system. In this case, you need to visit a service center, where professional installers will sort out the issue and fix the problem.

How to disable door lock

The function of automatically locking doors when the ignition is turned on is not always useful and many owners tend to disable it. Deactivation of this option on the Starline A91 Keyless alarm system is carried out through the programming menu. To do this you need:

press the Valet button five times with the ignition off, and then turn it on again;
listen to five vehicle beeps confirming the correct transition to this mode;
select the appropriate programming table using the third button on the remote control;
select option No. 2 – automatic control of door locks;
set the required parameter (4 – disabled);
turn off the ignition so that the system remembers the commands.

Now every time the car is armed, the doors will remain open.

Independent troubleshooting of alarm systems

It is often possible to fix the malfunction and remove the engine lock yourself if you can detect blown fuses. This problem often leads to malfunctions of the alarm system. The fuses must be checked; if a problematic element is detected, the blown fuse must be replaced with a known good one.
Malfunctions in the operation of the alarm can also be associated with insufficient battery charge or loose terminals on the battery contacts. In this case, the battery is still able to sluggishly crank the starter, but the engine blocking may already work and further prevent the engine from starting.

Another step is to check the limit switches (limit switches), which are located under the hood and trunk lid. Moisture ingress or oxidation of the limit switch often causes an incorrect signal to the alarm control unit, which leads to engine blocking. Please note that unprofessional installation of alarms and limit switches, as well as improper engine washing can lead to malfunctions of electrical equipment.

Technical methods for unlocking engine starting

The engine starting system in a car alarm is blocked by:

via CAN bus with complex programming of modes;
by starter (starter solenoid relay circuit breaker relay);
along the fuel pump circuit;
along the power supply circuits of injectors and injectors.

There are more sophisticated interlocks: in the limit switch of automatic transmission modes, in the power and communication circuits of the immobilizer, in the break in the circuits of the engine control unit. Such locks are made either on an individual order or during self-installation. The bad thing is that in most cases they are forgotten, and then unlocking them is extremely difficult.

In any case, work must begin by gaining access to the head unit of the car alarm. It is usually located under the dashboard, behind the fuse and relay box, to the left of the pedals in the lower left corner of the cabin, behind the trim. The place chosen is usually extremely inconvenient for work.

Additional fuses and relays should “hang” near the head unit. You should start by checking them. Sometimes it takes a lot of effort to get to them. You need to soberly assess your capabilities. Something like this may appear before your eyes.

It is necessary to separate all the standard wires from the alarm system, if possible, remove it closer.

It is necessary to check the connections between the alarm wiring and the standard electrical wiring of the vehicle. If the connections are poor, the connection may be broken.

The quality of the alarm installation can be judged by the quality of insulation of the connection points. Experienced installers place the wire connections in heat-shrinkable tubes (more mechanically reliable, moisture does not penetrate into them).

If an alarm system is installed that operates via a CAN bus, when this bus is disconnected, the blocking may be removed automatically. You should check this option. To do this, it is necessary to disconnect all contacts from the alarm head unit.

If this option does not work, you need to look for all the relays that the alarm serves. They can “hang” next to the alarm unit or be fastened with a plastic clamp. If the alarm is installed poorly, the relay may look something like this.

In order to restore the blocking, you can close the blocking contacts of the relay yourself. To do this, you need to use the relay circuit located on its body. You can carry out this operation without a circuit if you have a multimeter at hand.

As a last resort, you can use a screwdriver or knife to open the plastic relay cover (there are latches there). Then you should press the relay armature with your finger, closing the contacts forcibly. Before this, of course, you should check whether the relay is activated when the ignition is turned on or started. If it works, opening it will be useless.

If your car is equipped with an alarm system with auto start, a possible reason for the start failure may be a malfunction of the immobilizer bypass. The electrical circuit for its inclusion can be organized using a sequential method.

In this case, a break in the wires leading to it can lead to the standard immobilizer blocking the start. Geographically, the lineman is usually located under the steering column, or hidden behind the relay and fuse box. You need to find it and check the wiring. If a keyless crawler is used, a software failure of the device may occur. Then you need to temporarily disable the auto-start function on the alarm.

Tips and tricks

If attempts to remove engine locks and start the engine are unsuccessful, then there is a high probability of a serious malfunction or failure of individual alarm elements. The result is random activation of engine locks, which cannot be disabled using standard methods. The faulty car must be taken to a service station, as removing the lock will require professional intervention.

The specified delivery can be carried out by tow truck. Another affordable way is to call an auto electrician who works on-site. Note that the final costs of paying for the service of on-site engine unlocking, disabling the car alarm, emergency opening of locks, etc. often turn out to be less than delivering the car to a service center by tow truck and paying for repairs at a technical center.

How to fix?

Before doing anything with the key fob or control unit, you need to initially carry out diagnostics and understand what exactly has gone wrong. At the same time, for each type of malfunction the verification process may be different.

The alarm is not turned off by the key fob

Car alarm won't lock doors

Using a multimeter, the integrity of the wiring from the controller to the actuators is checked. The lock drive motor and connectors are also checked for resistance.

If the wiring and door actuators are intact, we turn off and send the central locking unit to specialists. They will carry out a detailed diagnosis and carry out repairs.

"Signalka" does not recognize the opening of doors

Car alarm behaves unpredictably

"Signalka" is in working order, but does not confirm commands

How to set up and reset the alarm?

To get rid of software glitches in car alarms, you can reset the controller settings from the key fob. You can reset the settings from the key fob by holding down the buttons with the image of an open trunk and a snowflake. You need to hold them for three seconds, after which the siren will emit two beeps.

Relay for blocking the fuel pump from the alarm.

Edinochestvo » Thu Jun 04, 2015 23:19

I’ll say right away that I know almost nothing about electrics. The situation is as follows. The car had an Excellent City alarm. There was only one keychain left, and I somehow broke it. I found an advertisement for the sale of the same used alarm system. I decided to install it by stupidly moving all the contacts from one control unit to another. The new key fobs work great, but the car won't start because... the lock is activated - the fuel pump does not pump.

Tell me where to look for the fuel pump relay, and where the blocking relay may be located - directly next to the first one, or anywhere?

The alarm key fob does not work, what to do and how to start the car, some practical tips

If you can’t disarm your car and it won’t start, what should you do?

Hello, sometimes it’s useful to know how to act in a given situation; today we’re looking at a situation where the key fob for some reason refuses to unlock the car.

There are actually not so many reasons for this malfunction; many of them can be eliminated independently, without special skills.

The first step is to bring the key fob as close as possible to the transmitter; it is usually installed on the windshield and press the unlock button several times every couple of seconds.

If it worked, there are several possibilities why it happened.

Dead batteries in the key fob. You are in a place where many things block the signal, such as an airport. The transmitter is faulty. The key fob is faulty.

The alarm is blocking the fuel pump, what should I do?

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And they - these algorithms - can be passive or active. Everything is the same as with well-known “minorities” - like relays and relays - and lo and behold - it can be “passive”, or maybe “active”. It depends on the algorithm (such as, on the environment, on upbringing) who will become who and what. The active blocking algorithm is the most vulnerable, because the blocking relay with such an algorithm in a de-energized state allows the engine to start.

This type of blocking is otherwise called “normally closed”, or simply NC - according to the type of blocking relay contacts in the “Security” mode. A typical implementation diagram of the NC engine blocking is illustrated by the fragment of the connection diagram for a standard Taiwanese alarm system shown in Fig. 2 - mostly manufacturers who have narrow eyes from birth like to use NC blocking.

In the “Disarmed” mode, there is no voltage on the blocking terminal, and therefore on the relay winding, and the relay, with its NC contacts (contacts 87a and 30), allows the engine to start. More precisely, it does not prevent this. In the “Security” state, there is a ground potential on this wire, and when you try to start the engine, a plus from the ignition switch will appear at the second end of the winding, the relay will switch, thus prohibiting the operation of the starter, in this example.

To neutralize active blocking, obviously, it is enough to simply de-energize the alarm module in any way. For example, by pulling out all the connectors from the module, or simply breaking the wires, and often it is enough to remove the system fuses from the holders. And that’s it – nothing can stop you from starting the engine. This is the main reason why I can’t stand blocking NC by relay contacts.

With a passive algorithm, a blocking relay prohibits engine operation in a de-energized state; the contacts of such a relay are normally open (blocking is therefore called NR).

Doesn't start with key

Your car won't start? The Starline alarm system performs a full autostart, but when started with the key, the car refuses to start.

First of all, you should park the car and put the gearbox in the “park” position. After this, put the car on the handbrake. It is worth taking the key out of the ignition and making sure that the car does not stall. If the car stalls, it means that the alarm is not configured correctly, because after the owner takes the key out of the ignition, the car must run for 30 seconds to give the owner time to close the doors and trunk, as well as park the car to the alarm. In this case, you need to come to a specialized center and report that you need to set up an alarm system. An auto electrician will help you set up the alarm in a matter of minutes.