1. What is UNECE / ECE R23?

ECE R23 is the European approval standard for reversing lights. It defines the technical requirements a lamp must meet to be legally used as a reversing light on vehicles across the EU.

2. Purpose and Scope of the Regulation

A reversing light must give the driver sufficient visibility when backing up in the dark, while also warning other road users—without dazzling them.

ECE R23 therefore defines:

• minimum and maximum light intensity
• beam direction and spread
• light colour (always white)​
• visibility angles​

It also imposes limits to prevent glare for other road users.

3. Practical Application

• A lamp with a valid E-mark and R23 marking (e.g. E20 23R-00 1757) is officially approved as a reversing light across the EU.
• Member states such as Belgium and the Netherlands may not deviate from this: once approved, the lamp must be accepted everywhere.
• The installation parameters (height, width, number of lamps) are defined under ECE R48.

An R23 lamp is typically connected directly to the vehicle’s reverse signal, so it switches on automatically when reverse gear is engaged.

4. Combination with Work Lights

Some lamps combine a work light function with an R23-approved reversing function, each with separate wiring. In this case:

• the R23 wire connects to the reverse gear signal,
• the work light function is operated separately via a switch and is not part of the R23 approval.

A lamp that is exclusively R23-approved avoids interpretation issues during inspection and is always legal as a reversing light. These lamps often produce 500–1000 lumens, which is more than enough to serve as a practical work light on non-public roads.

5. Summary

ECE R23:

• defines the legal standards for reversing lights,
• ensures EU-wide recognition,
• limits glare with strict beam and intensity criteria,
• and remains valid even as R23 is gradually replaced by R149

Tip: Always check the E-marking on the lens and follow the installation guidelines under ECE R48.