Auxillary electrical quirk?

[Leyland1980]

This is probably going to have to be a personal battle as everything relating to this issue was put in by me so it will definitely be my fault but I though I would ask for suggestions of where to look first.

I have a double cab 110 (2004) with an alucab over the load bed.

I recently added 2 led work lights to the rear and 6 led strip lights (2 on each door/hatch). The alucab is quick release (if you have the time and the strength) and all the electricary is connected by way of a 14 pin trailer hitch. The positive feed comes from an aux battery which says it is charging and holding charge well. The strip lights are simply switched from a panel in the alucab whilst the work lights are either switched through a single relay or activated as reversing lights when the headlights are on through 2 relays. This all worked very well with the work lights being brighter than day and the strip lights being more than adaquate.

The problem with which I require assistance is:
I have just put the alucab back on after a brief "lightweight" phase and whilst the lights all work in their switched modes ( albeit with successive dimming as you switch on each light I.e. 1 strip light bright, 2 strip lights less bright etc, work lights very dim) however in the reverse mode the work lights do not come on.

I have not yet got involved with the multimeter but any suggestions of where to look or potential issues would be gratefully received.

Cheers all

John

[130man]

Hi John, first stop is to check your earth pathway. If that is ok, and I usually connect from the plug direct to the battery for that check, try a direct connection from your battery to the lights, one at a time. Led lights draw so little current that they should not dim as an extra one comes on, so there is certainly a problem with voltage there. Hope this helps. Ross.

[drivesafe]

Hi John and can I suggest before you do anything, draw up a rough schematic of your wiring.

You may see the problem in the drawing itself or it may help track down the problem.

BTW it sounds a bit like a possible earth problem, but this is a wild guess at this stage!

[Leyland1980]

Cheers guys,

I had thought/guessed earth and checked the chassis part of that but need to check the bits in the trailer plug and socket too.

[Dervish]

It very much sounds like an earth problem as everyone has noted. Find where the earth from the trailer plug attaches to the chassis and make sure it's clean and tight. Chuck some copper grease on it for longevity, or better still run the earth wire all the way back to the battery.

[Leyland1980]

Thanks all, turned out to be a loose earth inside the trailer plug.

Only a couple of strands still making contact.

All better now.

Cheers

John

[drivesafe]

Hi John and lucky you found the weak point.

Situations like that cause fire in worst case, so you did yourself a big favour finding the problem before it got to be a much bigger problem.