Guide · Automotive components

LV 148 — the 48 V counterpart to LV 124.

Mild hybrids and powerful auxiliary units brought the 48 V vehicle electrical system. LV 148 defines the electrical tests for it — as a complement to LV 124.

Safeguard an automotive component

What LV 148 governs

LV 148 is the VDA test standard for electrical, electronic and mechatronic components in passenger cars (up to 3.5 t) with a 48 V vehicle electrical system. Like LV 124, it was developed by the manufacturers Audi, BMW, Daimler, Porsche and Volkswagen as a common basis.

Relationship to LV 124

LV 148 complements LV 124: the change of voltage to 48 V mainly requires adapted electrical tests (corresponding to Part I of LV 124). The remaining test areas — mechanical, climatic, chemical and service life (Part II of LV 124) — apply unchanged and do not have to be redefined for 48 V.

Why 48 volts?

48 V systems deliver more power with smaller cross-sections — for mild hybrids, electric compressors, active chassis and more. More power also means: careful EMC design of the switching paths.

Frequently asked questions

Do I need both LV 124 and LV 148?

For a 48 V component, the electrical tests from LV 148 are authoritative, while the mechanical/climatic/chemical ones still come from LV 124. In practice, the two interlock. We clarify the exact framework (often as an OEM derivative) on a project-specific basis.

And what about EMC?

Here too, EMC is governed by CISPR 25 and ISO 11452 as well as the ECE-R10 framework — regardless of the electrical-system voltage. At 48 V, the power electronics deserve special EMC attention.

Sources: testxchange — LV 148, LV 124 / LV 148 compared. The valid version or the OEM derivative is authoritative.