You don't have to do anything for the UK MOT. Auxiliary lighting is not tested - only compulsory lighting, unless the auxiliary light(s) in question comes on with (simultaneous to) one of the mandatory lights (dip/main/sidelights), then it becomes testable. So as long as the auxiliary light(s) is either separately switched (independent of mandatory lights), or if wired into one of the mandatory lights, it must have an isolating switch (in the off position when presented for the test).

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