Hi Milligan23 & welcome to the forum.
In answer to your post…
1. The Manual says we must inspect ALL reversing lamps. If there are clearly more than one lamp fitted, all must work.
2. There is no better brake than one which will lock the wheel. So if more than half the wheels in the service brake system lock, and the unlocked wheel is not giving a low reading (30% lower) then that system passes regardless of the total % required.
There is no imbalance fail for the parking brake. If both wheels lock then the brakes have achieved their maximum potential, so again it doesnt matter if the % is lower than 16%, as said there is no better brake than one which locks the wheel.
3. Headlamp aim, and reduced light output due to a product on the lens are two seperate failures and should be assessed individually, with seperate failure defects listed as applicable.
4. There is no distiction regards “commercial” tyres on Class 4 vehicles, be it a car or a van, unlike Class 7 where we need to check the suitability of load capacity. Test to the usual requirements of same sizes across an axle.
Hope that helps.
