---
kind: "section"
citation: "49 C.F.R. § 393.79"
title: "49"
number: "393.79"
heading: "Windshield defrosting and defogging systems."
url: "https://uscodex.org/cfr/49/393.79"
---

# §393.79. Windshield defrosting and defogging systems.

- (a) **Vehicles manufactured on or after December 25, 1968.** Each bus, truck, and truck-tractor manufactured on or after December 25, 1968, must have a windshield defrosting and defogging system that meets the requirements of FMVSS No. 103 in effect on the date of manufacture.
- (b) **Vehicles manufactured before December 25, 1968.** Each bus, truck, and truck-tractor shall be equipped with a means for preventing the accumulation of ice, snow, frost, or condensation that could obstruct the driver's view through the windshield while the vehicle is being driven.

## Notes

### Amendments

[70 FR 48054, Aug. 15, 2005]

### Authority

Authority: 49 U.S.C. 31136, 31151, 31502; sec. 1041(b), Pub. L. 102-240, 105 Stat. 1914, 1993; secs. 5301 and 5524, Pub. L. 114-94, 129 Stat. 1312, 1543, 1560; and 49 CFR 1.87.

### Source

Source: 33 FR 19735, Dec. 25, 1968, unless otherwise noted.

### Amendments

[70 FR 48054, Aug. 15, 2005]