Correct as at 2nd May 2024. It may be superseded at any time.
Extract taken: from Vehicle Inspection Portal > VIRMs > In-service certification (WoF and CoF) > Heavy trailers > Lighting > Daytime running lamps
4-4 Daytime running lamps
Reasons for rejection
Prohibited equipment
1. A trailer is fitted with daytime running lamps (Note 1).
Note 1
Daytime running lamp means a lamp designed to emit a low-intensity light forward of a vehicle to make it more easily seen in the daytime.
Summary of legislation
Applicable legislation
Prohibited equipment
1. A trailer must not be fitted with daytime running lamps (Note 1).