184001923 - E2020 DIRECTION INDICATORS/HAZARD WARNING LIGHTS - DESCRIPTION

Description

The left and right direction indicators are switched on by raising or lowering the special lever on the left of the steering column switch unit; the function is activated with the ignition in the ON position.The hazard warning lights (left and right direction indicators operated simultaneously) are activated via a button in the centre of the dashboard between the climate control system controls and all the direction indicators are activated at the same time. An LED at the back of the control button also comes on synchronized with the flashing of the exterior lights; this function is always activated.The turning on of the direction indicators/hazard warning lights is managed by the Body Computer which also controls the flashing frequency which is sent to the other nodes via the CAN serial network.The two "direciton indicators" in the instrument panel are also lit up in this way; the system also provides a low frequency acoustic signal in conjunction with the activation of the lights.

The direction indicators check function checks that the lights are working properly: the following are checked for each of the two circuit (right side branch and vehicle left side):

  • open circuit or missing bulb
  • short-circuit to earth (bulb s.c. or wiring s.c. to earth)
  • short circuit to battery voltage (wiring short circuited to Vbatt)
When one of the situations described above is ascertained, the Body Computer makes the failure status available to the CAN: in the instrument panel: a special failure warning light comes on and, at the same time, the information is shown in the display only at the key on.In addition, at the same time as a failure warning light comes on, the flashing frequency of the visual indication in the display and the acoustic signal increases; the flashing frequency of the exterior lights and the LED in the emergency button, on the other hand, remains unchanged.
the direction indicators are also used to signal that the commands sent by the remote control have been received and/or to signal a manoeuvre not carried out by the "passenger compartment access" control system.    See E3040 CENTRAL LOCKING.