Defrosting and defogging a windshield
The federal defroster rule, and where to look for your controls.
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The federal rule
FMVSS 103 says: "This standard specifies requirements for windshield defrosting and defogging systems." It says: "Each vehicle shall have a windshield defrosting and defogging system."
Which vehicles
FMVSS 103 says it applies to "passenger cars, multipurpose passenger vehicles, trucks, and buses."
Check it before winter
NHTSA says: "Make sure defrosters and all windshield wipers work and replace any worn blades."
Your controls
Defroster and climate controls differ by vehicle. Your owner's manual describes yours. NHTSA says: "Be sure to review your vehicle's owner's manual for more information on your vehicle's technology and safety features."
A clear view
FMVSS 205 says one purpose of the glazing standard is "to ensure a necessary degree of transparency in motor vehicle windows for driver visibility."
Cleaning the inside
We have no official source with steps for cleaning the inside of a windshield, and we give none. Follow your owner's manual.
FAQ
General information only. We are not a glass shop, insurer, or agent, and we do not schedule, quote, or refer. Whether your policy covers glass damage, and what you would pay, depend on your policy and your insurer; read your policy and ask your insurer or agent. If your vehicle has driver assistance features, follow your vehicle maker's instructions and owner's manual on any calibration after glass work.
Next: winter windshield care
NHTSA's winter checks.
