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Discussion Starter #1
As the title really. Last couple of days the interior lights in the back and the front centre one are on while driving. They also stay on for about 15 mins after the car is locked and charging.
The back ones dim slightly when I push the buttons on them (as in you can tell what's on and what's off) but don't go off altogether.
I'm sure I'm missing something simple so was just wondering if anyone else has had a similar issue??
Thanks in advance!

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Ampera aka IGOR
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I have heard of LED bulbs staying slightly illuminated when switched 'off'. I would check that they are switched off when the car is powered up, the car will automatically cut power to interior lights, boot light and sockets after being powered off for a short time. Next job would be to check the type of bulb fitted. If you have had the car from new then they will be old-style incandescent, if you bought it used then a/the previous owner may have 'upgraded' the bulbs to LEDs.
 

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Discussion Starter #3
They're all definitely in the off position when the car is powered on yet all still glow.
I've attached pics.
Will inspect the bulbs next but seems strange that all three have suddenly started doing it together and at the same time. I could understand the bulb being at fault if just one was doing it but the fact all three are seems weird.


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Given that all of them are on looks like a fault with the control circuit, can you check the voltage at the lamps?
Normally these things are a 'charge pump' circuit that drives an FET, when you open the door the FET turns on, which turns on the light, the charge pump keeps the FET on when you close the door, as the charge pump falls away the FET gradually turns off giving the dimming effect you normally see.
If your FET has started leaking then the light will be on all of the time, which is what you're seeing, If you're seeing 12v at the lamps then the FET has failed, you might find the whole thing is built into a relay that can be replaced time to check the service manual wiring diagram
 

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Discussion Starter #5
Given that all of them are on looks like a fault with the control circuit, can you check the voltage at the lamps?
Normally these things are a 'charge pump' circuit that drives an FET, when you open the door the FET turns on, which turns on the light, the charge pump keeps the FET on when you close the door, as the charge pump falls away the FET gradually turns off giving the dimming effect you normally see.
If your FET has started leaking then the light will be on all of the time, which is what you're seeing, If you're seeing 12v at the lamps then the FET has failed, you might find the whole thing is built into a relay that can be replaced time to check the service manual wiring diagram
Thanks buddy, will check the voltage and see what it reads

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Discussion Starter #6
Just been out and it now shuts them off when I leave the car but they're still on dimly when I drive.
Would that still point to the faulty FET you mention?

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Ampera aka IGOR
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@black_amp 's explanation is more detailed than my suggestion and more chance of being correct. Looking at the photos they appear to be a very white white if you understand me and not a yellowish white which makes me think they could be LEDs. I don't know if there could be any connection between the FET mentioned (it's a new component on me) and the LEDs, if they are LED bulbs.
 

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I think the car has a global shutoff at 15 mins to prevent parasitic drain on the 12v which is why they go out eventually. The manual was posted here so there will be a procedure for fixing interior light staying on problem. Which you need to look at for next steps ( FET is a field effect transistor )
 

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A thought that springs to mind is an earthing fault (resistive earth connection) which could allow a small voltage to accrue when the supply side is supposed to be off which may be enough to drive led lamps a bit. As both clusters are effected it would mean the earthing could be at the control box end. I have no idea where that is but I would unplug and replug all relay type plugins in the fuse panel for a start to clean up the connections.


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