Before doing anything, ask yourself this. Why is headlamp aim too low. Headlight aim doesnt change over the lifetime of a car unless something has happened. Some reasons below

Has the car been in an accident?

Has the headlamp unit been changed?

Has the bulb been changed, if so has the replacement been correctly fitted?

Has the car got Xenon or Led headlight bulbs? If so the self levelling may be faulty. If the car has any clever features like adaptive headlights where the beam pattern moves or adapts based on speed etc then the headlight or a sensor may be faulty. In any case there may be a complex procedure required that requires use of a diagnostic tool.

Most MOT testers charge nothing if its a simple case of turning a screw as with basic halogen lamps.

But who calibrates your expensive beam setter?

I've been caught out several times with dodgy beam setting machines in car and bike testing stations where I KNOW the headlights are correct to the spec having set them to the diagram, but the beam setter says they are too high/too low etc.

I once went back for a retest on a motorcycle and had a right moan and the answer was:-

"Errm - yeah well our machine was faulty last week so we have a new one and here's your pass certificate"

A wall, a tape measure and a calculator doesn't lie.

And

mattersoftesting.blog.gov.uk/the-mot-headlamp-aim-.../

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