SAE J2174â„¢ MAR2026 establishes minimum requirements for electrical distribution systems used in dollies and trailers measuring 2032 mm or more in overall width, including single or multiple trailer configurations for 12 VDC nominal applications. The standard covers wiring, cables, connectors, terminals, seals, coverings, and related system components, while addressing voltage drop, connector durability, salt fog, thermal cycling and shock, oil absorption, salt water immersion, steam cleaning, pressure washing, vibration, insulation resistance, tensile strength, connector pull force, misengagement force, and terminal retention.
It also provides requirements for conductor sizing, corrosion protection, sealing, routing, mechanical support, environmental protection, connector polarization, splicing, and installation practices. This edition was issued in October 1993, revised in February 2020, and reaffirmed in March 2026, superseding SAE J2174 FEB2020.
Application Scope: Use for the design, evaluation, manufacture, testing, and installation of 12 VDC nominal electrical wiring and distribution systems for heavy-duty trailers, dollies, trailer combinations, lighting circuits, ABS power circuits, and related truck-trailer electrical interfaces.
