Degraded modes for vehicles fitted with a light sensor

Loss of VAN CAR 1 network between the steering column switch module and the BSI

If communication between the steering column switch module and the BSI fails, the BSI activates the automatic dipped headlamp switching-on function.

Loss of VAN CAR 1 network between the BSI and the BSM

If communication between the BSI and the BSM fails, the degraded operation of the lamp switching-on is described in the following table:

Sensor fault

As soon as the sensor is considered faulty, the following strategy applies:

If the automatic lamp switching-on function is activated:

• when a fault is detected, the lamps switch on and stay on until the ignition is switched off ("off" position),
• if the lamps were already on when the fault is detected, they stay on until the ignition is switched off,
• if the driver deactivates the automatic lamp switching-on function after a fault is detected, the lamps do not switch off; they stay on until the ignition is switched off.

If the automatic lamp switching-on function is disabled:

• a sensor fault does not switch on the lamps,
• if the sensor fault was present when the automatic lamp switching-on function was activated, the lamps switch on immediately.

ABS ECU fault or loss of CAN network

If a fault is detected on the distance travelled or vehicle speed information, the lamps switch on immediately provided the instantaneous light levels from the upper and front sensors remain below the tunnel entry light thresholds respectively.

(see automatic lamp switching-on / switching-off conditions).