Filament monitor

In the event of filament breakage in a brake light bulb, REC (701) detects that current in the circuit is low. REC sends the bus message "Left brake light not working ON" or "Right brake light not working ON", depending on which circuit is faulty. This bus message is used by SID to show a warning message in the display. If there is filament breakage in a bulb that normally functions as a brake light, its function is handled by the adjacent parking light and a message is displayed in SID.

Fig 1: Identifying Filament Monitor

Courtesy of SAAB-SCANIA OF AMERICA, INC.

If there is a break in the circuit of the high-level brake light, REC (701) detects that current in the circuit is low. REC sends the bus message "Center brake light not working ON". This bus message is used by SID, which shows a warning message in the display.

NOTE: REC (701) cannot determine whether individual LEDs in the high-

level brake light are not working.

IMPORTANT: When changing a bulb, use one with the right output otherwise the components could be damaged.