For the brake light switch, the measure to prevent a contact point failure in the presence of foreign material is not sufficient, and therefore, if the outside of the switch body is touched by a working glove that has handled insulating grease, the grease may gradually diffuse and reach the contact point. If this occurs and some insulating material is generated on the contact point, the braking light might fail to illuminate and it might become impossible to shift the gear lever out of the parking position.
