haulrecordFMCSA data

Violation codes / 393.78

49 CFR 393 · Parts and accessories

393.78

What it means

Wipers - Inoperative / missing / damaged wipers

What the rule actually says

This violation cites 49 CFR 393.78, windshield wiping and washing systems. The regulation reads:

(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 wiping system that meets the requirements of FMVSS No. 104 (S4.1) in effect on the date of manufacture. Each of these vehicles must have a windshield washing system that meets the requirements of FMVSS No. 104 (S4.2.2) in effect on the date of manufacture.

(b) Vehicles manufactured between June 30, 1953, and December 24, 1968. Each truck, truck-tractor, and bus manufactured between June 30, 1953, and December 24, 1968, shall be equipped with a power-driven w…

The section continues.

49 CFR 393.78, Windshield wiping and washing systems. Read the full section on eCFR

Quoted verbatim from the Electronic Code of Federal Regulations. Nothing here is a paraphrase, and nothing here is legal advice on a citation.

Times recorded152,31533% as often as 393.9, the most cited
How common8thof the 200 most cited codes, out of 2,372 that exist
Regulation393.78Parts and accessories

How often this comes up

This violation was recorded 152,315 times across the roadside inspections in the FMCSA file, making it the 8th most frequently cited code. Whether a given instance puts a vehicle or driver out of service is decided at the roadside by the inspector, not by the code itself, so the same violation can end a trip or simply be noted.

It sits under 49 CFR Part 393, which covers parts and accessories. To see it in context, look up a carrier and read its inspection history: the same code appearing repeatedly is a different signal from a single occurrence.

Look up a carrier's inspection record

Other parts and accessories violations

Counts are from the FMCSA Inspections and Violations file via data.transportation.gov. This describes how the violation is recorded, and is not legal advice on a citation.