The 42-volt electrical system was proposed to replace the standard 12-volt system in passenger cars. As cars added heated seats, electric steering, and active suspension, electrical load skyrocketed. Tripling the voltage to 42 volts allows components to draw less current, which means manufacturers can use thinner, lighter wiring harnesses. However, safety concerns over electrical arcing and the high cost of components stopped the transition. Modern mild-hybrid cars instead use 48-volt systems.
Mechanic Glossary
42-Volt Electrical System
A proposed automotive electrical standard developed in the 1990s to replace the current 12-volt standard to meet higher power demands.
Frequently Asked Questions
They were never widely adopted because of concerns over switch arcing and the high cost of redesigning vehicle components.
Higher voltage reduces current draw for the same power. This allows the use of thinner, lighter wiring throughout the car.
Modern cars use 48V systems for hybrid components alongside standard 12V systems, combining safety and high-power delivery.