Re interior light timer

Doesn't the above actually only indicate that switched +ve and switched -ve are effectively in series, thus whichever cuts off first turns lights off?
Thats very probable but the bit I don't understand is when CH38 is set to 1 (30 sec) then the -ve is shutting down my LED's (as they're not wired to the +ve) as expected and it's only when CH38 is set to >21 that it behaves differently. It's like something else is overriding this CH38 setting causing the -ve to cut off after 10 minutes.
Whatever is causing this doesn't affect the +ve feed and it doesn't make sense in so much that leaving the cargo switched to ON with the CH38 set to 254 would mean it stays lit for over 2 hours! So why this mystery 10 minute cut off on the -ve??

I mentioned earlier in this thread that I had a suspicion it may have something to do with the power draw of the LED's (which total about about 24w) and am wondering if the BCM is seeing this draw and is cutting the -ve after 10 minutes to save battery which might explain why your test bulb and low wattage LED's are behaving differently.
Luckily I fitted a 3 way switch to the LED's, left pole to -ve, centre pole empty (off) and right pole to permanent ground (for lights when camping) which means I can at least test this theory sometime this week by switching my LED's off and testing first the OEM halogen then maybe a low watt LED bulb in the OEM cargo fitting switched to courtesy to see if it will go past this 10 minute override situation.
Will let you know how it goes.

Have you tried disconnecting starter battery for a few minutes?
To reset the BCM? Not yet, but will give it a go if my testing above yields the same results.

I had an idea to feed my working lights from leisure battery but then rejected the idea because I assumed leaving a door open (for a day/night) would have drained the battery - because assumed "switched -ve" would purely be "door open" signal. But based on these experiments now I could use "switched -ve" to turn off also consumers on leisure battery.
Well at least some good has come from this experience so far. :)
 
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Hi, I might be hi-jacking this thread - apologies if so, please point me in the direction of the right place. I am replacing the 2x original load bay lights with LED courtesy lights and a genuine VW step light. I did the step light a while ago, works fine. I then added an LED above the sliding door, on a 3-way rocker switch (to retain the on/off/door functionality). See badly drawing wiring diagram of my mods, attached. When I open the door, the LED comes on at the expected brightness. Last night when I fitted it, it came on for around 30 secs, then dimmed-off, along with the step light and cab lights. When I switched it to 'on' it came on but very very dim, unless I did this within 30 seconds of opening the door, whereby it was very bright. I also found that if I turned it 'on' (dim) then briefly touched the original filament bulb across the connections to the new LED, its brightness increased dramatically. Might be worth noting that at this point, the engine battery was pretty low and I had not put the key in the ignition at any point during the installation. May also be worth noting that I had to use the negative from the chassis, rather than the loom, due to inability to route all of the cables through pop-top surround. I thought this might be a resistance-sensing thing...... however.......
Next day......
I drove the van to work (45mins) and found that after this, the LED came on at the expected brightness, in both switch positions. The timer delay however had now increased to around 10 minutes, until the lights all dimmed to off (which from reading this forum seems normal) so all appears to be ok....

Any ideas?!

I plan to fit 2 of the same new LED lights by the tailgate next, on one 3-way switch.

Assistance greatly appreciated!!

Jim

P.S. I know some people have had issues with the LED glowing when 'off' when making similar modifications, but I do not have this issue currently.

Interior Lighting Modification.png

 
Hi.

Found this thread while searching.

My T6 van has always behaved OK with the rear courtesy lights in the back. I open the doors, the lights come on and stay on for plenty of time before turning off. Recently, I open a door, the lights come on, and I swear less than 30 seconds they go off. Shut door, open it again, they’re back on. Very annoying. It’s been in to the garage recently for engine issues, but I can’t imagine they would have changed anything .
 
Just going by my recent experience, my lights stayed on for around 30secs when I hadn’t driven it for a while so battery was low. I charged it and they went back to normal. How’s the health of your battery?
 
Just going by my recent experience, my lights stayed on for around 30secs when I hadn’t driven it for a while so battery was low. I charged it and they went back to normal. How’s the health of your battery?
That does make sense. Hadn’t realised they would have considered that in the design. The battery is only 18months old, but recently has struggled a tad with starting. It’s always started, but does feel limp at times.
 
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