Jump to content

Boot light


DensYeti

Recommended Posts

My take on the boot lock / switch is that the car knows the boot is open / shut as interior lights dim and Maxidot displays correctly. Therefore the problem is not that.

My suspicion (in my case) is a damaged wire somewhere between the boot lock switch and the actual light.

I have evidence that the interior trim has been removed and refitted (prior to me fitting a towbar) and that the previous owner (second owner) had issues with the boot light (apparently resolved by changing the boot light itself).

When I had the trim out, the interior light did work for a while which surprised me. But I inspected and wiggled a number of wires to see where the problem was, but found nothing...

Link to comment
Share on other sites

Flexing of loom where it exits the door in the elephant like trunking at the top of said door?

As the car reliably knows when the boot is open and (as far as I know) the power lines for the interior boot light don't go through that trunking, I'd discount that one.

Link to comment
Share on other sites

I believe though (this is  only going by the Fabia circuit diagram) that the full current for the light bulb does pass through theswitch mounted in the tailgate? If there is a 'resistive' switch or it's wiring (though not high enough resistance to prevent the 'boot open' detection) this could cause those symptoms?

 

Maybe a further check would be to (with the tailgate shut) to earth the 'earthy' side of the bulb. Does the light come on and does it also give a 'boot open' indication?

Edited by muddyjim
Link to comment
Share on other sites

How is the trim on the tailgate held on?  Is it like the trim panel by the drivers right ear where the seat belt anchorage goes through?  That bit of trim has spring steel blades bent in half and opened out to form a V shape so that the V pushes into holes in the body and holds by friction  (found one of those just flattened between trim and body.....poor workmanship on behalf of garage I bought car from and who replaced something to do with seat belt before I bought it.......there is still a rattle by my right ear so they must have left something loose)

Link to comment
Share on other sites

The tailgate trim is a bigger to get out without breaking the two blocks/tabs at each end. It's hard to describe, but be gentle with it.

I stand corrected on my assumption about the cable runs - I now don't recall there being any cables under the tailgate trim. I'll double check photos from when I fitted the towbar, but this would indeed mean the sensor must be run through the trunking by the boot hinghes.

However, if the car reliably knows the boot is open/closed is faulty wiring to the sensor going to be the problem?

Or does it point more towards faulty wiring to the actual light?

Link to comment
Share on other sites

How to get trim off???

Has anybody got a picture or can describe the fixings.

 

Last time I tried to get trim off in a Golf it was only after I got it off having broken tabs before I could see I could have done it without breaking anything.

 

It looks like the light problem could be to do with the microswitch in the picture in the other thread mentioned.

I would like to check the circuit on the tailgate/mechanism.

Dennis

Link to comment
Share on other sites

How to get trim off???

Has anybody got a picture or can describe the fixings.

Last time I tried to get trim off in a Golf it was only after I got it off having broken tabs before I could see I could have done it without breaking anything.

Me to on my Yeti!

If you look on here for people fitting towbars (mine included) you may find suitable photos to help you stop breaking anything. Sorry, but I can't work out how to get a link to a specific post in my original thread.

Basically, you need to pull the bottom corners of the boot lip trim towards the front of the vehicle to disengage the two clips circled red. Be gentle with them as the connecting blocks behind the trim is not very robust.

post-59543-0-78807800-1484496997_thumb.jpg

Edited by KBPhoto
Link to comment
Share on other sites

Sorry but that just says to "unclip trim" using the special wedge tool.  What is needed is a picture of the clips so we can see just how they fit.

I remember the VW Golf ones came apart once you knew what they looked like but were easy to break if you did not know.  

Link to comment
Share on other sites

Me to on my Yeti!

If you look on here for people fitting towbars (mine included) you may find suitable photos to help you stop breaking anything. Sorry, but I can't work out how to get a link to a specific post in my original thread.

Basically, you need to pull the bottom corners of the boot lip trim towards the front of the vehicle to disengage the two clips circled red. Be gentle with them as the connecting blocks behind the trim is not very robust.

attachicon.gifIMG_8664.JPG

Just to clarify; the latch mechanism & switch is within the tailgate, so the trim on the tailgate itself needs to be removed to gain access....

 

JIm

Edited by muddyjim
Link to comment
Share on other sites

Isn't the clip shown in post 35 above?

Ah - sorry I didn't see the picture first time.  However I can't really see what I am looking at or what clip is shaped like or what it fits into......probably obvious once you have trim off and can actually see the clip..(like it was on the Golf)

Link to comment
Share on other sites

That picture in post 35 is of the trim at the rear of the boot floor, not the tailgate trim? I'm not sure removing that trim is going to reveal much that would help with a potential microswitch issue?

Edited by muddyjim
Link to comment
Share on other sites

My bad for posting a picture of the wrong part. Sorry.

As already posted, this thread has the official instructions for the correct part: http://www.briskoda.net/forums/topic/288429-removing-tailgate-interior-trim/

Edited by KBPhoto
Link to comment
Share on other sites

Muddyjim.......thanks. Magnified the photo and clips quite clear.  Still not sure how they are held in the turrets in the trim though. (they are not the same clips as the Golf )

 

Anyone know what the fork trim removal tool looks like? I presume it would squeeze the two sides of the clip together to make easier to remove with less stress on the trim.

 

So far diagnosed the problem is between the light unit and earth.  With tailgate open I can light the lamp by earthing direct with a piece of wire from neg side to tailgate lock pin.

Can measure12V on supply side and negative side with tailgate lock manually triggered shut;  11.75V negative side to earth with tailgate open but light dosn't come on (i.e. 4.5V drop across light unit.  It must be a bad earth - I would suspect the microswitch high resistance corrosion at contacts or corrosion where wire connected to earth.

 

I am going to give up as I am chickening out trying to get the trim off....I do not want to damage it.

 

Pity as I would like to put some silicone grease on the lock mechanism plastic rotating bits (photo in a thread on replacing a broken lock mechanism)

 

Thanks again to all.

 

Dennis

Link to comment
Share on other sites

The clips look to me exactly the same as the ones that hold the boot side panels on - spring steel strips bent to vaguely an 'omega' shape. If it's the same as the side panels they are fitted to the trim by sliding sideways into the trim 'turrets'. I've attached a photo showing a clip on my side panel and you can see how it attaches into the slot sideways.

 

post-128817-0-54690700-1484673697_thumb.jpg

 

The official removal tool that is shown in the manual is part no 3409 and looking on ebay is basically a plastic wedge and you simply slide it between the trim and the tailgate to force the trim to unclip. As said elsewhere if you attempt this it is probably best to do it in warmer weather when the plastic panel isn't so brittle.

 

http://www.ebay.co.uk/itm/VW-Disassembly-Wedge-3409-Original-Special-Tool-VAG-wedge-Matra-Volkswagen-Audi/111998399702

 

Jim

  • Like 1
Link to comment
Share on other sites

The luggage compartment light ground side is connected to a switch in the lock unit and to the onboard supply unit module. That electronic module provides the 'dimming' (pulsed ground)  when the lid closes and the lock switch is open circuit. The positive side of the light is common with the glove box light.  There is indeed a diode in series with the  lamp and a positive voltage +12V should be on the end of it.

 

1. Remove the bulb.

2. Does the the glove box light work? If no there is a +12volt supply problem - check for blown fuse.

3. If yes, is there +12 volts on one side of the luggage compartment lamp holder at the lamp contact?. If no the diode is open circuit.

4. If yes and with the lamp removed, is there near zero ohms to ground (usually a brown wire) on the other side of the lamp holder when the lid is closed?

5. If no, the lock switch or wiring to it providing the ground return path is open circuit.

6. If there is no low resistance but a fluctating reading, that could be the auto lamp dimming operating o.k and the switch in the lock must be faulty (open circuit?).

 

Don't mess about adding external ground wires because you might risk damaging the electronic onboard supply unit module responsible for lamp dimming and other things!

Edited by voxmagna
  • Like 4
Link to comment
Share on other sites

To voxmagna......thanks

 

My earlier post (No.7) shows some readings I took earlier.

The fault is almost certainly between earth side of light plug and earth and seems most likely to be the lock switch whose contacts have gone high resistance due to slight burning when opening, so not allowing enough current to light the bulb.

I will wait for warmer weather to attempt to remove tailgate trim for further investigation...............hey ho back to a nice warm bed to hibernate.....its good being retired.

Link to comment
Share on other sites

Lock switch contacts are usually pretty crude wiping contacts that can get grease or oil on them from the lock or over enthusiastic lock spraying with WD40. They might be cleanable. The only reason they might burn is if a lamp filament went short circuit?

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
  • Recently Browsing   0 members

    • No registered users viewing this page.
  • Community Partner

×
×
  • Create New...

Important Information

Welcome to BRISKODA. Please note the following important links Terms of Use. We have a comprehensive Privacy Policy. We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.