Interior lights nightmare!

[Fessey83]

I have a mk6 transit swb 85 T280 on a 06 plate, when I bought it the interior lights did not work so I checked the fuses and found that the fuse was blown, replaced it and both interior lights worked fine in the cab, I then replaced both load bay lights and got those working too, one night last week I came home from work locked my van and went inside, at four in the morning the missis was up with the baby and looked out of the window to notice my interior light was on, so I ran out with a bat thinking that somebody was trying to steal my pride and joy!, just to find the van securely locked but with the interior light on, this flattened my battery and it would not start. I noticed the lights never went out when I locked the van and narrowed it down to the light near the bulkhead in the front, it would not turn on or off no matter what position the switch was in so I took the bulb out thinking job done lol, the lights went out when I locked the van. Woke up in the morning and the van was as dead as a dodo not even ignition lights! So I gathered that somehow the load bay lights were on all night which I obviously couldn't see. I don't want to just pull the fuse so none of my internal lights work, I want it to be right but what's wrong! Any help is much appreciated.

[ake]

Either one of the door latch switches is faulty,or you have a broken wire in a door loom, most likely the rear door loom. The ecu thinks a door is open so it switches the lights on

[jls security]

The front cab interior light unit fitted nearest the rear , controls the load bay lights. Im betting it is that fitting that is also at fault. Easiest way to see if rear lights have been staying on is to see if the fittings are hot. Or. Simply close all doors except side loader. Lock the van and keep the door switch pressed in on side loader at same time ( fitted to van body at rear lower closing edge) all lights should then go out

[winterheating]

Even if a door is left open, or it thinks s door is open the lights should go off anyway after 20 mins or so.

When leaving them on by leaving them switched on, the rear lights should be identified being on by the rear cab light being on.... The wires could have been removed and put on the wrong way on the switches at some point...
Normally the switches fully forward to be activated by doors, ( the light should also immediately go off when turn ignition on in this position, or when all doors are locked)
Middle position is off.

Position at the back of switches is to keep on constant, I remember this as it points to back(load area) so when you want the lights on constant in load space.
But even in this position eventually the lights will go off, about 60 mins or something, all to save battery I would imagine just like the radio time limit too.

So only way the lights could possibly stay on all night is if a relay was stuck of something....????

Both my vans interior light operating relay is the bottom left under dash , but they are old vans not 06's so prob yours different.

[Fessey83]

thanks for all your responses, i have removed the bulbs from the load bay lights and with all your info im gonna keep digging and find the problem, battery was that dead this morning i had to put the code in my cd 6000 player! im beginning to think that the lights in the back were disconnected for a reason when i bought my van! ill post the fault when i find it and thanks again people

[toopstar]

My load bay lights dont go off if the doors are open, even after an hour or more, they do turn off when the doors are shut because i have old screw holes in the bulkhead so i can see they are definitely not on. My solution was to fit LED lamps instead of the standard bulbs, not quite as bright but could be left on for days or more and wouldnt screw the battery!

[winterheating]

Do an acual battery voltage check the battery may not be getting charged to full capacity.
Even stranger on a mk7 that the interior bulbs would be allowed to stay on more than an 1hour..

[SNOWDOG]

Dont get me started !!! my interior lights dont work with the doors or locks since i had the fuel pump renewed
the cab lights work 'manually' but thats it
Took it back to the garage and complained, everything was working before etc etc.... but after watching them poke about with it for an hour and they were still scratching their heads, i said, bollox doesnt matter and left
i have to add, that this was after it took them SIX weeks to do the pump i even thought at some point after numerous phone call excuses that something evil had happened to my van
But i had it back, it was running and i wasnt going to leave it with them Ever again.
Seven years ago now, Still no lights