SAE J1128

SAE J1128 is a U.S. automotive wire standard established by the Society of Automotive Engineers (SAE) for low-voltage electrical systems in passenger cars, trucks, and off-road equipment. It specifies construction, performance, and testing requirements for primary wires in 12V and 24V systems.

The standard includes wire types such as GPT, GXL, SXL, and TXL, which vary in insulation thickness and temperature ratings. These wires are widely applied in control circuits, lighting, dashboards, engine compartments, and power distribution throughout vehicles.

Designed for demanding automotive environments, J1128-compliant wires provide abrasion, chemical, and heat resistance with flexibility across operating ranges from -40°C to +125°C. Trusted by OEMs and harness manufacturers worldwide, SAE J1128 ensures reliable, safe, and durable vehicle electrical systems.