When hooking up last week the brake lights on the van were really dim ,I cleaned the electric hook up on the car but no difference I couldn't see any obvious problems .any idea's ?
If you remove the rear lens there should be a collection of bulbs in one long holder. There will be wires going to the base which are the earthing points so just remove each wire independently, clean with a small wire brush or smooth sand paper and apply a spray of WD40 to them and also inside the wires as WD40 is safe to use on electrical components. Whilst the rear light cluster is removed it may pay you to remove each bulb and do the same as well as if there is any surface corrosion it may affect with bulbs in the near future.
A similar thing happened to my caravan last year just on one of the indicators so I removed both rear lenses and cleaned the lot so should be okay for another few years hopefully.
When I cleaned each bulb I used wire wool and Brasso (metal polish) which made the bulbs look like new then sprayed WD40 into each bulb holder as they are difficult to clean manually. I would also advise to spray a little WD40 into the car 12 volt socket and corresponding plugs on the caravan as it also expels any damp as well as cleaning the contacts.
WD 40 should not be used on plastic parts as it hardens the plastic and causes it to crack as petroluem base kills oil in plastic. use a similar type of product from electrical wholesalers does same job but does not attack plastic. contains tiger oil not the striped kind
I took the light cluster off and the terminal was not quite connected to the brake light so I sorted that and cleaned the terminals and the problem was sorted ,thanks again .