Brake light wiring problem.

[DaveT]

We have moved up from camping, after our last disaster and have bought a 2001 Abi Brooklyn 600eb. So this is all new to me.
The problem I have is the brake light Wire on the near side rear seems to have a bad / loose connection somewhere.
I have taken all the connectors off cleaned them and replaced the bulbs but the problem seems to be inside the hole that the wiring goes into the caravan? Not a very good description... how do I get to the wiring inside to check it? Does anyone have any ideas please

 

[Damian]

Have you checked the connections in the plug to the car for security and damage?

You could check each circuit at the rear lights by disconnecting each power feed to each light, one at a time, and put a multimeter between the power feed to each light in turn and the white Earth and see if you have power.
You would obviously need some way of actuating the brake light, either another person or a length of wood to hold the brake pedal down.

Also, have you checked the fuses just inside the van where the cable goes in at the front, usually under the front seating area at one side.

 

[ProfJohnL]

It's unlikely to be the wires, as Damian points out its more likely to connectors either at the cars plug and socket, or at any place the cable is jointed. all of which should be accessible without having to remove wall boards etc.

 

[DaveT]

Thanks so far for the replies Have had plug to connect to car changed
I’ll try describe the problem a bit better..... the lights are all working apart from the brake light. It works intermittently. When the foot brake is applied constantly, the brake light goes on and off when the wires are moved.
It seems to be where the wires go into the hole into the wall I’m not sure if there are connectors inside and am just unsure how to get to them?
Iv looked inside the van, the bathroom is at the rear. But again no joy in finding anything.
There are screws along the bottom of the wall outside but again not sure if I should be taking these out to find anything.

 

[ProfJohnL]

It would be poor practice to have a connector hidden in an inaccessible location such as inside a wall panels with no access. Having said that I cannot guarantee that caravan manufacturers don't do such silly things. I think i'd be checking the crimp connectors on the light fittings. - especially the 0V lines

 

[Damian]

I have not come across any van which has connectors anywhere other than at either end.
Normally the lighting cable for the road lights is one continuous length from light connections right through to the fuse box inside the van at the front, and then to the plug to the car.

Some vans have the cable routed inside the van, but most have it under the van attached to the underfloor as that is the most protected route.

Quote " Have had plug to connect to car changed" The question is, who changed the plug and was it tested immediately after being done.
That statement alone rings alarm bells in my mind as to whether or not there is a problem with the connections in the plug, loose wire, not enough insulation stripped off, wrong position in the plug.

 

[DaveT]

It would be poor practice to have a connector hidden in an inaccessible location such as inside a wall panels with no access. Having said that I cannot guarantee that caravan manufacturers don't do such silly things. I think i'd be checking the crimp connectors on the light fittings. - especially the 0V lines

ov lines.? What are those?
I’ll change the crimp connector see if that works.
thanks again

 

[Damian]

Ov lines are the earth wires, normally the white ones which is common to all the roadlights.

I actually hate it when people use more technical terms for things, just stick to basics and what most people understand.

 

[Tuningdrew]

Quite possibly a broken wire just inside the rear panel. Seen it occasionally on older cars on unsupported wiring runs. The insulation hardens and wire can fracture. No alternative but to go digging.

 

[DaveT]

Quite possibly a broken wire just inside the rear panel. Seen it occasionally on older cars on unsupported wiring runs. The insulation hardens and wire can fracture. No alternative but to go digging.

thanks mate,
it seems like iv said ,I think there’s a loose wire somewhere, iv just been up again and it’s now blown the fuse on my car, rav4 rear lights twice while checking the lights .
would a loose wire be the cause of this?
getting really frustrated with it just now
😖😖😖

 

[ProfJohnL]

A loose (i.e. broken) wire that's flapping around could possibly cause a short circuit and blow a fuse, but if its flapping around that much its unlikely to always return to make the bulb light.

Does it only happen when the caravan is moving?

It's a long shot, but have you tried changing the bulb?

 

[Tuningdrew]

The fact it’s blowing fuses to me indicates a short circuit, possibly chafed wires where the wires pass through the caravan bodywork or is clipped to the caravan chassis. Is the caravan hitched onto the car while you’re doing your checking? If it is then the 12v wire to the bulb may be making contact with the metal chassis somewhere and shorting to earth via the towing hitch. If you can find someone who can use a multimeter it can be checked out quite easily to prove the point but you’ll still need to physically check the cable.

 

[ProfJohnL]

I'm inclined to agree with T. But if it's happening when the caravan is just standing (no movement what so ever) then it's more perplexing.

I've had house wiring chewed by mice, it's possible you might have had an infestation.