Internal lights issue

[thisischeese]

Recently, I've discovered an issue where the internal rear lights don't turn off with the ignition. Instead, they stay on flashing/flickering.

 

On other occasions, the headlights have also stayed on when the ignition has gone off - more than the 'coming home' function.

 

Annoyingly, we forgot to manually turn off the internal lights yesterday and the alarm started sounding at 23:00... not ideal.

 

Anybody know where to start with identifying and resolving this?

 

For context, I have installed LED boot lights and a CarPlay box from Aliexpress, in case either of these are relevant.

 

Octavia VRS, 2014, TDI

 

 

(Apologies if this has ben addressed elsewhere, but I couldn't find anything in the search)

[Warrior193]

Hello @thisischeese, did this problem start around the same time you fitted the LEDs and the CarPlay? 

[thisischeese]

Hard to say because I only use the internal lights for young passengers once the clocks go back and it's darker. It wasn't happening last year in the darker months and I installed them since then.

 

Swapping the original lights back is a simple test actually. Although will be frustrating if that's the issue because the originals are next to useless for actually seeing anything.

[Warrior193]

I'd be inclined to check the CarPlay unit first.

If it does turn out to be the LED trunk lights, don't give up - there are compatible LEDs available, I have changed them on the Octavia and the Fabia - I agree, the OEM lights are pretty useless.  

[thisischeese]

You don’t realise just how bad they are until you swap them out!

 

Not really sure where to start on the CarPlay unit. It’s all wired in as it should be. I might do some research on any potential issues before ripping it out again though. 

Electrics in cars drive me mad!

[Warrior193]

Was it just the trunk lights you replaced - or did you also replace the interior, cabin ones ? (map lights, etc.)

Can you just pull the fuse for the CarPlay unit?

Edited 5 December, 2023 by Warrior193
added information

[thisischeese]

Just the trunk. All others are original as far as I’m aware. 
 

Could it be a voltage issue with LEDs being lower???

 

The battery is probably original too

Edited 5 December, 2023 by thisischeese

[ords]

How old it the battery?  Might be worth getting it checked out.

[Warrior193]

8 minutes ago, thisischeese said:

Just the trunk. All others are original as far as I’m aware. 
 

Could it be a voltage issue with LEDs being lower???

 

The battery is probably original too

I believe the issue with some LEDs can be electrical 'noise'

There is often a date stamp (YYMM) on one of the battery posts. Correction - the date format might be MMYY.

Edited 5 December, 2023 by Warrior193
correction

[thisischeese]

Thanks for your input, I’ll take a look at the battery in the daylight. 
 

Last time I tested the battery back in August, it was on 54% health

[thisischeese]

Digits on the negative post are 26 14, so I'm guessing it's the original battery on there.

 

Nearly 10 years for a battery is probably good value, but time to suck the cost of a new one. I know the cranking is low on it and that's probably why it takes a few seconds to start.

 

I'll change that and see if that helps the lights issue, as it needs doing anyway.

[Warrior193]

Does your car have stop-start (is the battery EFB/AGM) type?

[thisischeese]

It does have start/stop and it's and AGM.

 

I've ordered a new one from Tayna because I figured it's due a replacement anyway.

 

EDIT - this is the current one, not the new one!
 

Edited 6 December, 2023 by thisischeese

[Warrior193]

Fair to say that the old battery has done pretty well. For the record, do you tend to use the stop-start function most of the time?

[ords]

2 hours ago, thisischeese said:

It does have start/stop and it's and AGM.

 

I've ordered a new one from Tayna because I figured it's due a replacement anyway.

 

EDIT - this is the current one, not the new one!
 

This is the exact same battery I have. Original battery and showing no signs of giving up, altho having said that now🙂  S/S used all the time.

[Warrior193]

And there was me thinking my 7 yr. old Moll EFB was doing OK - but, then, it is a Moll 🤔(presumably not one of the duff ones)

[thisischeese]

S/S is on all the time (unless my toddler is asleep and don’t want to risk waking her!). That being said, I do tend to fall into a habit of not letting it kick in most of the time by lifting the brake ever so slightly. 
 

Maybe with a new battery it’ll be a bit ‘fresher’ on the restart as well. 

You’ve tempted fate on your battery now…

[thisischeese]

New battery fitted (only minimal swearing involved). Starts like a dream now, so worth doing.

 

Lighting issue remains though, but the plot thickens...

 

Thought I'd try locking with the light on whilst sat in the driver's seat, then noticed that it seems to think the boot is open/closing (see video attached). Basically keeps flashing up with the boot open graphic.

 

When it's stopped raining, I'll go and test the boot lights (and once I've found the originals in the garage, because obviously I didn't throw them away and obviously I can't remember where I put them...)

[ords]

Did you code the battery?

[thisischeese]

14 minutes ago, ords said:

Did you code the battery?

 

No, I decided to go with the 50% of people saying it would be fine. Especially as it's a like for like battery swap. Errors that came up disappeared after 20 metres. Will ask my VAG specialist to check it next time it's in though.

[J.R.]

Your problem could be caused by the replacement LED bulbs and its quick and easy to swap back to prove or disprove.

 

Otherwise having seen the Maxidot video its quite possible that the rear hatch lock microswitch has a dodgy contact causing the door open visual and the interior lights to flash.

 

I upgraded to LED cargo lights on the last 2 cars, on this one it still wasn't enough and was hampered by the solid luggage cover so I used some self adhesive 6 LED strips, I cut them into 3's and fixed them with tiny screws and spliced into the feed wires.

[thisischeese]

The culprit has been found.

 

Took out the LEDs and also put the originals back in. In both instances, the interior lights go off with the ignition and there's no tailgate latch warning.

 

I've contacted the ebay seller to see what they say. Maybe the £8 was the initial warning...

 

For anyone that's done this before, it's just a simple plug and play right? I don't have to worry about the two cables they come with if the plugs fit, right?

 

Any recommendations of where to buy 'legit' ones or what to look for?

 

[Ray Luxury-Yacht]

1 hour ago, thisischeese said:

The culprit has been found.

 

Took out the LEDs and also put the originals back in. In both instances, the interior lights go off with the ignition and there's no tailgate latch warning.

 

I've contacted the ebay seller to see what they say. Maybe the £8 was the initial warning...

 

For anyone that's done this before, it's just a simple plug and play right? I don't have to worry about the two cables they come with if the plugs fit, right?

 

Any recommendations of where to buy 'legit' ones or what to look for?

 

Are there maybe resistors contained within those plugs?

[PetrolDave]

2 hours ago, thisischeese said:

Any recommendations of where to buy 'legit' ones or what to look for?

I fitted these from Kopacek on my previous Octavia estate with no problems.

[Warrior193]

1 hour ago, Ray Luxury-Yacht said:

Are there maybe resistors contained within those plugs?

No, the resisters are usually mounted in the light section itself - I had the same adaptors supplied with my LEDs - which worked without problems (without the adaptors) in the both Octavia and Fabia. The adaptors are for fitting to vehicles with different cabling. The only issue I had was having to trim the aperture a little so that they fitted correctly.  

@thisischeese I will look up the details of the supplier I got mine from.  

Edited 12 December, 2023 by Warrior193
added information