Boot Open Warning when Glovebox / Vanity Mirror Opened

[rajb]

Hi all.

Hoping someone may have an idea of this very strange issue.

So recently I started noticing the boot open warning randomly (or so I thought) coming on when driving. Checked the bootlid each time and all ok. Started to link it to every time my wife was sat in the car and then realised that its because she always for some reason opens the vanity mirror and leaves it open and this was the trigger. Then tried the glovebox and same thing. So whenever you open the glovebox or vanity mirror the boot open warning triggers. As soon as you close them all good again.

Am really stumped so any help/ideas welcomed.

Thanks,

Raj

[Watts]

See this thread which has a solution: https://www.vwroc.com/forums/topic/10403-opening-glove-box-causes-boot-open-warning/

 

[rajb]

See this thread which has a solution: https://www.vwroc.com/forums/topic/10403-opening-glove-box-causes-boot-open-warning/

 

Yeah did come across that but his last post said the fault had occurred again after the replacement of the part they thought it was.

[wantmygti]

Hi Raj, I had this exact issue with my glovebox and I did manage to resolve it.

Firstly, I noticed the issue disappeared for a period after charging the battery. This lead me to suspect the battery which I changed, but the issue prevailed albeit less often.

Having gone back to square one I did a bit of digging online and found someone who had this issue after swapping their boot light to a ‘no errors’ LED light. I had done the same. As soon as I took out the boot light and replaced the original light the issue went away.

If you have replaced the boot light with an LED version I would start there. Next up I would have the same suspicion of any interior light you have swapped to LED - I never noticed an error with the vanity mirror but I’m. It sure I ever tried. I think the error relates to these LED lights that draw a little power even when the boot (or doors) are closed, making the car think they could be open. Quite why the glove box triggers it I’m not sure, must be something to do with the glovebox or vanity light LED coming on putting the circuit voltage above a threshold??

[rajb]

Thanks for the reply buddy. Very appreciated and you know what I literally just swapped out a boot LED light for standard this morning as I remembered swapping this out last year and didn’t even come into my mind till I stopped to think of everything that’s been done before the issue. Thing is it didn’t kick in till quite sometime after so never put the two together as the culprit.

Crazy how it caused the issue but only when the glovebox or vanity mirror were opened/on.

We’ll all sorted now thank heaven as was driving my potty trying to work it out.

 

[golfdave]

Maybe the resistor in the aftermarket LED isn't a high enough value?  I fitted an aftermarket LED to my boot light & the LED still lit up very dimly. As I have the estate its in the roof lining, so would see it in rear view mirror at night! I soldered a nice resistor across the bulb contacts. Different lights in the car are told to switch off by the BCM, whilst others are switched directly by the lock switch.

Quote from my build on the MK7 Golf forum:-

The car came will all LED interior lighting..except for the glove box light & the rear boot light. Now the glove box light is a straight swap out & replace with the footwell LED unit which I did when I got the car. The boot light did not have a straight LED replacement light unit, & I still currently can’t find an OEM LED version! VAG appears to be using several of the footwall LED units in the bigger top end car boots!

So when I got the car I fitted a good LED “bulb” (Philips X-treme Vision LED 43mm festoon). However this always remained dimly lit when the ignition was on, or off & the cars main ”X” relay had not timed out. This is because the light is powered directly from the BCM & not the lock switch. So the light is “told” to switch off instead of a mechanical/physical break in the wiring like a switch! This means there is a very small milliamp supply still in the cable from the BCM which would not be enough to light the OEM incandescence bulb, but is enough to light the LED! Now I knew that the best way around this was a resistor to stop the milliamp supply, but I never found out the correct resistance & wattage to use in this situation, & the web was filled with conflicting “facts”.

So wind forward 4yrs to now, & this “mod” has been tried even more times on the web, so the facts are clearer! Basically in this situation a 1000ohm 0.25watt resistor is the most suitable, & wired across the “bulb” contacts. As the resistor can generate a very small amount of heat (0.25W) I decided to wire the resistor across the LED bulb itself & through the built in heat sink. This heat sink is electrically isolated so safe for the resistor to sit in. This also means the resistor is covered by two metal items, the heat sink & the OEM reflector. Result?....it works..no more dimly lit LED!.

https://www.golfmk7.com/forums/index.php?threads/vw-golf-mk7-estate-gt-spec-tungsten-silver-1-4tsi.326479/page-7#post-6767303

[wantmygti]

Thanks for the reply buddy. Very appreciated and you know what I literally just swapped out a boot LED light for standard this morning as I remembered swapping this out last year and didn’t even come into my mind till I stopped to think of everything that’s been done before the issue. Thing is it didn’t kick in till quite sometime after so never put the two together as the culprit.

Crazy how it caused the issue but only when the glovebox or vanity mirror were opened/on.

We’ll all sorted now thank heaven as was driving my potty trying to work it out.

I had the same - the LED boot light was in for maybe 4 years before it started causing the error. I don’t understand why the time lag unless the LED unit somehow failed.

[rajb]

Maybe the resistor in the aftermarket LED isn't a high enough value?  I fitted an aftermarket LED to my boot light & the LED still lit up very dimly. As I have the estate its in the roof lining, so would see it in rear view mirror at night! I soldered a nice resistor across the bulb contacts. Different lights in the car are told to switch off by the BCM, whilst others are switched directly by the lock switch.

Quote from my build on the MK7 Golf forum:-

The car came will all LED interior lighting..except for the glove box light & the rear boot light. Now the glove box light is a straight swap out & replace with the footwell LED unit which I did when I got the car. The boot light did not have a straight LED replacement light unit, & I still currently can’t find an OEM LED version! VAG appears to be using several of the footwall LED units in the bigger top end car boots!

So when I got the car I fitted a good LED “bulb” (Philips X-treme Vision LED 43mm festoon). However this always remained dimly lit when the ignition was on, or off & the cars main ”X” relay had not timed out. This is because the light is powered directly from the BCM & not the lock switch. So the light is “told” to switch off instead of a mechanical/physical break in the wiring like a switch! This means there is a very small milliamp supply still in the cable from the BCM which would not be enough to light the OEM incandescence bulb, but is enough to light the LED! Now I knew that the best way around this was a resistor to stop the milliamp supply, but I never found out the correct resistance & wattage to use in this situation, & the web was filled with conflicting “facts”.

So wind forward 4yrs to now, & this “mod” has been tried even more times on the web, so the facts are clearer! Basically in this situation a 1000ohm 0.25watt resistor is the most suitable, & wired across the “bulb” contacts. As the resistor can generate a very small amount of heat (0.25W) I decided to wire the resistor across the LED bulb itself & through the built in heat sink. This heat sink is electrically isolated so safe for the resistor to sit in. This also means the resistor is covered by two metal items, the heat sink & the OEM reflector. Result?....it works..no more dimly lit LED!.

https://www.golfmk7.com/forums/index.php?threads/vw-golf-mk7-estate-gt-spec-tungsten-silver-1-4tsi.326479/page-7#post-6767303

Nice reply buddy and thank you. Certainly appears to be the linked to resistance as it was only with the LED bulb. Happy to keep the stock one and not worry about it for now lol.

[rajb]

I had the same - the LED boot light was in for maybe 4 years before it started causing the error. I don’t understand why the time lag unless the LED unit somehow failed.

Yeah may well be a failing unit as tbf the LED unit I had was secondhand and given to me when I bought the Aero under trays from a fellow member. All sorted now at least.