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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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.

What to do if the engine does not start after turning off

If all of the above measures do not lead to the unlocking of the engine starting system, then the problems with the car are probably more serious, and you need to quickly deliver the car to a service station, where it will be possible to carry out a full diagnosis of the anti-theft device and important systems of the car, determine the real reason for the engine blocking and eliminate it.

To deliver your car to a service station, it is better to use a tow truck. You can also invite an electrician or anti-theft systems specialist to your garage.

In conclusion, it should be noted that the anti-theft system is reliable and functional only if installed and connected correctly. Any error in installation and settings can block the engine and create many problems. To avoid troubles, choose a car alarm from trusted manufacturers, trust its installation only to professionals, and if malfunctions occur or the car’s engine is blocked by the alarm, use only proven unlocking methods.

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.

Unlock methods

Having installed an external alarm system, for example, Starline, it is advisable for the car owner to carefully study the instructions for the rules of its use and operation. The instructions also contain tips on what to do if there is a malfunction in its operation.

The easiest way to unlock an external alarm is to re-close the car doors. To do this, get out of the car and close the door tightly. Then turn on the remote control to arm the car and wait about ten seconds. It is during this time that the car is armed. On some types of alarm systems, the arming process takes longer, from one to two minutes. Open the doors again using the remote control and try to start the engine. If the failure occurs due to the door switches, hood, or trunk lid, then the car will start.

An attempt to return parameters to factory settings using the key fob can work effectively. Due to the fact that there are very many types of alarm systems installed on cars, and at the same time the settings algorithm is also varied, resetting parameters and returning to factory settings must be carried out according to the instructions.

Situations arise when the central unit does not respond to commands sent by the key fob. In this case, you can use the Valet service button. The button may be located in a secluded place, where the hijacker will not find it and it will take time to find it through the wires.

The location of the Valet button is indicated in the description, but often installers choose its location at their own discretion. It is recommended that after installing the alarm, you check with a specialist in what place he placed it. Forgot to ask or bought a used car, and then there were problems with the signaling. No problem - the service button is easy to find along the wires coming from the central unit.

If the alarm system is blocked so that not only the engine does not start, but the doors do not open, then you need to open the door lock with the key. Opening the door will automatically trigger a loud sound alarm, which can be turned off by disconnecting the terminal from the battery. Using the dialing method or using a diagram, the terminal numbers on the central unit and the color of the wires are determined. Using this information or visually using wires with the corresponding color, we find the location of the button.

Switching to service mode (or unlocking) is individual for each type of anti-theft system. Therefore, how to use the Valet button is described in the manufacturer’s instructions. Basically, all actions are almost the same for most types of alarms.

Here is an example of Starline deactivation:

Open the car with the key.
Turn on the car's ignition and press jack three times (time limited to 20 seconds).
Turn off the ignition.
The siren will sound and the emergency lighting will turn on at intervals.
Starline deactivation is complete.
Start the engine.

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.

How to unlock a car

The fact that it is the anti-theft system that blocks the engine can be determined by:

control light on the panel (abnormal flashing mode);
door unlock failure;
the sound alarm or headlights are triggered;
immobilizer failure or incorrect operation of the buttons on the key fob.

With the listed symptoms, it is immediately necessary to determine the cause of the malfunction. It may be enough to simply replace the dead battery in the immobilizer. If this does not help, then computer diagnostics of the signaling system is necessary: it may be installed with errors, and after 5-7 years of operation, it may begin to fail even with correct installation.

If there are no questions about the anti-theft system, then you should look for breakdowns in the leading systems of the car itself, to which the alarm is connected. For example, in some models of foreign cars, engine starting may be blocked due to a faulty starter, damage to the ignition circuits, incorrect operation of the fuel supply system, malfunctions in the ABS, etc.

If you do not have the opportunity to immediately take the car to a service station for diagnostics, you can use one of the proven options for “restarting” the anti-theft device to unlock the engine.

Disabling the lock with the service button

The simplest solution for unlocking the engine in an emergency situation is to reboot the alarm using a “rollback” to the factory settings (you can use the factory instructions for setting up and operating the alarm).

This unlocking option may work if the system head unit refuses to respond to commands from the immobilizer key fob. As a standard, the procedure can be performed using the Valet button under the driver's panel on the left. Necessary:

open the car with the key;
turn on the ignition;
press the Valet button three times;
turn off the ignition.

After this, a sound and light alarm should sound - this is a signal that the individual settings have been reset, the system has returned to the factory settings and is disconnected from the engine lock. Now you can try to turn on the ignition again and start the car engine.

Disabling the engine lock function

Another available way to unlock the engine in the field is to disable the alarm from the starting system. It can be connected in several ways:

using programmable modes via CAN bus;
through the starter solenoid relay breaker;
through the electrical circuits of the fuel pump;
through power supply to injectors or nozzles.

More complex connections are also possible through the automatic transmission limit switch, immobilizer power supply or engine control unit.

To turn off the alarm, you need to get to its head unit, which is usually installed under the driver's instrument panel, near the fuse box, to the left of the pedal unit or under the trim of the driver's seat. The operating procedure is as follows:

checking additional relays and fuses;
disconnecting standard connections from the signaling unit;
checking the connections and contacts of the signaling system with the car's electrical wiring.

If the anti-theft system is programmed via the CAN bus, then after disconnecting the connections, the engine will be unlocked automatically. If unlocking does not occur, you need to find all the signaling relays and force them to close according to the circuit or using a multimeter. Another option: check the operation of the relay when the ignition is turned on, and if it does not work, remove the cover of the signaling unit and press the relay armature to close the contacts.

Independent troubleshooting of alarm systems

What else can be done to unlock the engine? Experts recommend checking:

condition of the alarm unit wiring, clean oxides on the contacts, replace damaged metal wire clamps;
the relay reaction when turning the security system on/off from the immobilizer (clicks should be heard), and replace it if there is no response;
the condition of the mounted fuses next to the central signaling unit (possibly replace them);
battery charge and condition of terminals and connections to the battery;
the state of the fuses of the main electrical circuits and relays if the central locking or headlights do not work;
condition and serviceability of limit switches under the hood and trunk lid;
proper operation of the car's electronic control unit, spark plugs and starting system circuits, control sensors, compression and fuel pressure;
the serviceability of the immobilizer crawler and connection circuits (if an alarm with auto-start is installed), and temporarily disable the auto-start function.

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?

Re: Fuel pump alarm relay.

AtmoSTi » Thu Jun 04, 2015 23:30

Re: Fuel pump alarm relay.

GrammatonCRAFT » Thu Jun 04, 2015 23:38

Re: Fuel pump alarm relay.

AtmoSTi » Thu Jun 04, 2015 23:43

Re: Fuel pump alarm relay.

Edinochestvo » Thu Jun 04, 2015 23:59

Re: Fuel pump alarm relay.

AtmoSTi » Fri Jun 05, 2015 6:42

Re: Fuel pump alarm relay.

Edinochestvo » Fri Jun 05, 2015 9:53

Re: Fuel pump alarm relay.

crazy_energy » Fri Jun 05, 2015 9:58

Re: Fuel pump alarm relay.

AtmoSTi » Fri Jun 05, 2015 10:20

Re: Fuel pump alarm relay.

ssg5 » Fri Jun 05, 2015 12:42

Re: Fuel pump alarm relay.

Edinochestvo » Fri Jun 05, 2015 13:11

Yes, the car starts if you connect the old alarm unit. But what the hell, I’m now 1000 km away)

Re: Fuel pump alarm relay.

Edinochestvo » Fri Jun 05, 2015 13:12

Re: Fuel pump alarm relay.

tarasus » Fri Jun 05, 2015 13:47

Re: Fuel pump alarm relay.

623y » Sat Jun 06, 2015 2:21

A little about functionality

Old models (for example, Mongoose Imperium M5000), which require a standard immobilizer to ensure 100% protection, have been replaced by new products that can independently provide unprecedented security and two-way communication (Mongoose Base 20, Mongoose 600, Digital 100, Mongoose lq 200 and others).

Mongoose alarms of the modern line offer the user the most convenient and thoughtful set of options, namely:

Silent security mode. In this case, only light signals and a message on the pager alert you about the attempted theft (the sound is turned off).
Delayed security mode. The alarm will not turn on the protection immediately after pressing the corresponding buttons, but only after the trunk and doors are closed.
Automatic engine start. Systems with autostart Mongoose will turn on the engine according to preset parameters (at a certain temperature, at a specific time, set by an alarm clock or timer).
Anti-Hi-Jack mode (active, passive). Enabling this option blocks the engine while driving (this process is controlled by the owner, the mode is activated by the key fob buttons when attempting to steal).
Emergency shutdown . This mode allows you to remove protection from the car using a special PIN code, even if the car cannot be opened with the alarm key fob or in a situation where the control panel was lost by the car owner.

Firmware for the new Mongoose remote control

Reprogramming the Mongoose alarm remote control switch (Pentacle M-1, 600 Line4, 900 ES line 4, 600, PS 2070, 900ES, LS 9000D, LS 7000D, IQ215, 1.7R, 1.9R, EMS 7.0, vp commodore, ems 1.7, Transponder, MX750S, MX30T with 2 buttons, MX 200, base a50 1) follow the instructions.

Turn on the ignition. Using the service key, enter the password (the number of presses corresponds to the PIN value).
Turn off the car's ignition and turn it back on immediately.
On the transmitter, press the first button. A short siren signal will sound to confirm successful recording.
To exit the setup menu, turn off the engine and press the service mode entry key once.

Instructions

Anti-Hi-Jack. Robbery protection The mode can be turned on and off by programming. Note: In order for Anti-Hi-Jack to be activated, in addition to software enablement of the function, it is necessary to set a two-digit PIN code for the Mongoose DIGITAL 100 system. Your Mongoose DIGITAL 100 security system is equipped with a special anti-burglary function Anti Hi-jack, which will be automatically activated if any door is opened while the ignition is on. You can also turn on Anti Hi-jack remotely by pressing button 3 for 3 seconds with the ignition on. If the function is software enabled and you are asked to hand over the keys and leave the car, simply comply with the demands of the robbers, Anti Hi-jack will turn on the alarm itself and force the robbers to stop. To ensure that the activation of Anti Hi-jack does not interfere with the movement of the car and you have the opportunity to calmly turn it off, and also to avoid creating a dangerous situation on the road, the anti-theft procedure goes through the following stages until the full alarm is activated and the engine is blocked: 1 30 second pause for entering the disabling code. After opening the door or pressing button 3 on the control panel for 3 seconds with the ignition on, the warning lights will flash once. The system LED flashes slowly to remind you to enter the disable code. 2. Warning mode. If you have not entered the disable code during the 30 second pause, the system will remind you of this with short beeps over the next 30 seconds, and the LED will flash quickly. 3. Alarm mode. At the end of stages 1 and 2, if the disabling code has not been entered, the system goes into alarm mode: a full sound and light alarm is activated. When the simulated fault lockout (SSDA) mode is enabled by software, it will turn on simultaneously with the alarm. In this case, the engine blocking will be carried out according to the following scheme: 1 second - blocking ==> 5 seconds - pause ==> 1 second - blocking ==> 3 seconds - pause ==> 1 second - blocking ==> 2 seconds pause = =>1 second – block ==> 2 seconds – pause, etc. The last cycle will be repeated until the ignition is turned off, after which the engine will be completely blocked and it will not be possible to start until the Anti Hi-jack is completely turned off. If the fault simulation lock is disabled by software, the engine will be locked immediately after the ignition is turned off. The alarm mode continues until the Anti Hi-jack is completely turned off.

Disabling Anti-Hi-Jack: 1. To disable Anti-Hi-Jack during a 30 second pause 1, as well as during warning mode 2, without turning off the ignition, use the emergency shutdown button to enter the first digit of your PIN code by pressing it the appropriate number of times . If the code is entered correctly, after 3 seconds the signal lights will blink twice, the LED will go out, and the Anti Hi-jack will turn off. 2. If Anti H-jack is activated remotely, then during the first 30 seconds (before the start of sound signals), it can also be turned off by pressing button 3 again for 3 seconds on the same remote control that was turned on. 3. When the system is already in alarm mode 3, then to disable the Anti-Hi-Jack, regardless of the activation method, you must enter the full emergency shutdown code, having first turned off and turned on the ignition again. If an incorrect code is entered twice, the system will block further code entry for 2 minutes. The LED will blink twice

ATTENTION! If the Anti-Hi-Jack anti-theft procedure is activated, the system is blocked from executing any remote control commands. To temporarily prevent Anti-Hi-Jack from being activated, you can use Valet mode

How to start the engine if the security system has blocked the start

Software actions are usually powerless here; it is necessary to open the wiring and restore the factory connections of the wires. If the main alarm unit fails, it is necessary to restore the factory connection of the starter power supply circuit from the ignition switch.

The main alarm unit is connected to the gap in the thick red wire running from the ignition switch to the starter. In case of any glitches in the unit, just connect the specified wire back together and the engine will start. You can restore the connection in one of two places:

Disconnect the two thick red wires from the alarm unit and connect them together, twisting them and insulating them with cambric or electrical tape.
Disassemble the steering column casing, and near the ignition switch connect the previously broken two red wires, from the ends of which wires go to the alarm unit.

If the immobilizer crawler fails, it is necessary to restore the operation of the standard immobilizer antenna. To do this, it is necessary to dismantle the steering column casing, disconnect the wires going from the antenna to the radiator, and restore the integrity of the antenna.

For your information. The immobilizer antenna is a short loop of wire with a black or black and white sheath located near the ignition switch.