SAAB WIS ONLINE

Direction indicators, detailed description

Direction indicators, detailed description

The direction indicators are located in the headlamps, the front wings and the rear light clusters. Upon activation, CIM sends a message to the fuse boxes in the engine bay and luggage compartment, which control the direction indicators in the front and rear, respectively. Flash frequency is 90 flashes per minute. In the event of filament breakage, flash frequency is increased to 180 flashes per minute and a warning message is displayed in SID.


The direction indicators can be activated when the ignition switch is in the ON position. The direction indicator switch is mounted in CIM (703). When the direction indicator stalk is moved up or down, CIM (703) sends the bus message "Direction indicator stalk active RIGHT" or "Direction indicator stalk active LEFT". The bus message is used by BCM (707), which determines the flash rate. BCM (707) sends bus messages (see Direction indicators and hazard flashers, bus information ) which are used not only to control UEC (342) and REC (701) but also for MIU (540) indication and acousitc indication in the front speakers (266FL/FR) via ICM (736) and EHU (353).


Front direction indicators

The front direction indicators (27FL/FR) and side direction indicators (89LH/RH) are supplied power from UEC (342). The direction indicator function in UEC is controlled by bus messages from BCM. UEC activates the correct direction indicator output based on which bus messages are sent by BCM.

UEC supplies voltage to the front left direction indicator (27FL) from pin 3(F) and the side direction indicator (89LH) from output pin 4(F).

UEC supplies voltage to the front right direction indicator (27FR) from pin 2(F) and the side direction indicator (89RH) from output pin 9 (F).

Filament monitor

UEC supplies current in each circuit. In the event of filament breakage in the front left direction indicator, for example, UEC sends the bus message "Front left indicator not working ON" for pin 3(F). This bus message is used by BCM (707) and ICM (736). BCM doubles flash frequency to 180 flashes per minute. ICM displays a warning message in SID.


Rear direction indicators

Power is supplied to the rear direction indicators (27RL/RR) from REC (701). The direction indicator function in REC is governed by bus messages from BCM. REC activates the correct direction indicator function based on which bus messages BCM sends.

REC supplies power to the rear left direction indicator (27RL) from pin 8 (R-D) and to the rear right direction indicator (27RR) from pin 6 (R-D)

Filament monitor

REC measures the current of the respective circuit. In the event of filament breakage or the like, REC sends the bus message "Rear left indicator not working, ON" for pin 8 (R-D) or "Rear right indicator not working ON" for pin 6 (R-D). This bus message is used by BCM (707) and ICM (736). BCM doubles flash frequency to 180 flashes per minutes. ICM displays a warning message in SID.

Indicator symbol in MIU

MIU uses the bus messages "Activate front left indicator ON" and "Activate front right indicator ON" to activate the indicator symbol for the left or right direction indicator.

Acoustic indicator

ICM uses the bus messages "Activate front left indicator ON" and "Activate front right indicator ON" to send a bus message to EHU (353) to activate an acoustic signal in the front speakers (266FL/FR). ICM prioritises all acoustic indicator and warning symbols in the car. If a warning message comes while the direction indicators are active, the direction indicator tone is interrupted while the warning tone is active in the speakers. A warning tone has higher priority than the direction indicator tone.