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Alfa Romeo 145/146 Electrical System Diagnosis Manual, Volume 3 (1994-2001)02 · 146 electrical system diagnosis
02 · Diagnostics

Alarm mode

Make
Alfa Romeo
Model
145/146 Electrical System Diagnosis Manual, Volume 3
Year
1994–2001
Section
Anti Theft device › Alarm mode
146 electrical system diagnosisAlarm mode
  • checks that the ignition key is not being tampered with;
  • checks movements inside the passenger compartment (volumetric sensors);
  • only for versions without ALFA ROMEO CODE: cuts off the supply to the starter motor (provided that the key is turned to MARCIA) and deactivates the engine electronic control unit (Boxer 1.7 16 v version).

ALARM MODE

The system enters the alarm mode when one of the surveillance sensors detects an abnormal situation.

The alarm mode can trigger a warning system to the outside (activation of the siren and blinkers, with times varying according to the versions/markets). Only for versions without ALFA ROMEO CODE there are other countermeasures such as: cutting off the engine supply (Motronic control unit supply - Boxer 1.3 and 1.6 version - or stop solenoid valve supply and glow plug warning device - TD version).

The alarm ceases:

  • with a command from the transmitter (deactivation);
  • 25 min. after the last activation of the alarm mode;
  • by turning the emergency key.

(N.B.: in this case the alarm activated condition is stored in the control unit memory).

SELF-DIAGNOSIS

UPON ACTIVATION the system carries out self-diagnosis (indicated by the flashing of the LED at 4 Hz). If a fault is found, the LED will identify it through a special flashing code as shown in table 1.

F2 Type of flashingMeaning
8 Hz, duration 2,5 sec.Door/bonnet/tailgate left open or faulty switch
Fixed light, duration 2,5 sec.Faulty volumetric sensors
16 Hz, duration 2,5 sec.Fault in electronic control unit

When a door or bonnet/tailgate is found to be open/faulty or when a fault is detected on the volumetric sensors, the corresponding sensor is cut off by the surveillance mode and a beep signal is given one second after they are reactivated.

WHEN THE ALARM IS DISABLED

the dissuasion LED flashes to indicate which of the sensors triggered an alarm during surveillance (see table 2).

N.B.: the signal is cancelled turning the ignition key to MARCIA

F1 N. Flashes*Component with alarm
1 FlashRight front door
2 FlashesLeft front door
3 FlashesRh door rear
4 FlashesLH rear door
5 FlashesVolumetric sensors on ceiling light
6 FlashesBonnet
7 FlashesTailgate
8 FlashesKey-operated supply cut off
9 FlashesBattery supply cut off
10 FlashesAt least 3 causes of alarm contemporaneously

(* ) If there is more than one, the alarm codes are presented in sequence.

The flashes last for 0.5 sec. with an interval of 1.5 sec. between them.

In addition to the automatic SELF-DIAGNOSIS described here, it is also possible to check the system by MANUAL DIAGNOSIS (see "FAULT-FINDING").

INHIBITING THE INTERIOR SURVEILLANCE SYSTEM

It is possible to inhibit interior surveillance in one of the following ways:

  • a) in close sequence (prior to enabling the alarm system): starting from the MARCIA position, move the key to: STOP, MARCIA, STOP.

Confirmation of the inhibition of the interior surveillance system is given by the lighting up of the dissuasion LED for appr. 2 sec.

Parts & tools for this job For 1994 Alfa Romeo 145/146

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