S.4 Cab & Controls Study Group Information Report 2013-1: Mirror Obscuration During Inclement Weather

Equipment users have reported to TMC experiences of mirror obscuration during inclementweather. Testing has confirmed cab and mirror design contributes to the concentrated flow of air that can contain water borne dirt. Large windshield wipers sweep significant fluid off the windshield and into the air flow path of the mirror heads, resulting in dirt deposits on the mirror surface. TMC has determined that a generic field fix cannot be developed since the causal factors are different for each manufacturer’s vehicle design. Therefore, TMC recommends thatequipment users experiencing this problem should contact the manufacturer’s service depart-ment for the recommended field action applicable to their particular vehicle or vehicles.

Issued: October 2013