SAAB WIS ONLINE

Parking lights, detailed description, 5D

Parking lights, detailed description, 5D

The parking lights can be lit together with main/dipped beam or by themselves. The parking lights are lit when the light switch is in position 1 if the ignition is on. The parking lights are on in other light switch positions depending on the programming alternative selected.


The LEDs in the rear light clusters are supplied PWM-regulated voltage from an electronic unit in the light cluster.

The vehicle parking lights consist of the following lamps:


- In the front, lighting consists of light-emitting diodes positioned in a row in the top edge of the headlamp. The lamps are supplied power from the underhood electrical centre (UEC) (342).

- 15 LEDs (13) in each rear light cluster (418RL/RH). The LEDs are powered from the rear electrical centre, REC (701).

- Two lamps (15) for number plate lighting. Power is supplied to the lamps from the Rear Electrical Centre, REC (701).


BCM (707) uses pins A29 and A30 to determine which position is set. BCM (707) pin A29 is connected to light switch pin 4, which corresponds to position 0. BCM (707) pin A30 is connected to light switch pin 2, which corresponds to position 2. BCM (707) sends a bus message with information on light switch position. UEC and REC use this bus message to determine if parking lights should be lit based on the programming alternative selected. For more information on bus messages, see Parking lights, bus information.


The parking lights can be lit together with the headlamps or by themselves, regardless of the position of the ignition switch.

Front parking lights

UEC (342) uses the bus message regarding light switch position to activate the outputs. UEC supplies B+ voltage from pin 8 (F) and pin 1 (F) to pin 4 of the headlamps (663FL/FR).

US: UEC supplies B+ voltage from pins 5 (F) and 6 (F) to pin 1 of the side marker lights (234FL/FR).

Rear parking lights

REC (701) uses the bus message regarding light switch position to activate the outputs.

REC supplies B+ voltage from pin 12 (R-D) and pin 10(T-D) to pin 6 of the light clusters (418RL/RR). The LEDs for the parking lights (13RL/RR) with associated electronics are located in the light clusters. Power is supplied to the lamp for number plate lighting (15) from REC pin 10 (T-B).

REC feeds a B+ voltage to the light clusters. Each cluster contains electronics that are used to convert the B+ voltage to a PWM voltage of suitable pulse width and current. The frequency of the PWM voltage is around 130 Hz. Through the use of PWM voltage, the same LEDs can be used for the parking lights and the brake lights.

US: The rear side marker lights comprise 3 LEDs that are located sideways in the bottom of the light cluster. They are powered internally in the cluster from the electronic unit.

Filament monitor

If several LEDs fail, REC will detect the low current in the circuit. REC sends a bus message "Left tail light not working" ON or "Right tail light not working" ON, depending on the circuit that is at fault. This bus message is used by SID to show a warning message on the display.


The rear parking lights come on if the following faults occur:


- REC has no bus communication and the ignition is on.

- Fault in microprocessor