See also:

Replacing interior bulbs
Check the operation of all bulbs frequently. ...

Lamp assembly condensation
Exterior lamps are vented to accommodate normal changes in pressure. Condensation can be a natural by-product of this design. When moist air enters the lamp assembly through the vents, there is a p ...

Blocked sensor
An extreme build-up of materials on the left and/or right quarter panel fascias such as mud or snow can cause degraded performance of the BLIS . Also, heavy rain can cause the same effect. ...