Boot light problems with Fabia Mk 1 Estate

[prt57]

Hi,

I think I have the classic problem with the microswitch in the orange part of the boot lock in my Fabia Mk 1 Estate in that the lamp will illuminate intermittently when the boot is opened. I know that the green and brown wire from the bulb holder is a switched earth in the lock mechanism and so has anyone devised a fix for this apart from wiring in a manual switch?

Does anyone know the part number for the orange latch in the tailgate. With the internal cover in place the number is just hidden? Also what is the new cost of the orange latch as 2nd hand units will potentially have the same problem?

I would like to get this sorted as at the moment, this is the last thing to fix on this project car!

 

Thank you for your help.

[prt57]

I thought I’d update you with what I have found out. 

The photo shows that there are two micro switches in the electrical connection on the back of the tailgate latch. This part has just been unscrewed from the back of the latch. 

From my research about when the boot light will not work, there is confusion as people think  there cannot be a fault with the latch switch when the boot light does not work if the warning on the dash still illuminates. 

I have worked out that when the micro switch in the photo near the green wire is depressed by the white nylon cam the dash light illuminates and the other micro switch operates the boot interior light. So one works by being pressed in and the other one relies on the internal spring  pressure creating the contacts as the cam moves away. This is the switch for the interior light and so if there is poor internal spring pressure for some reason then poor contact results and the interior light will not illuminate. 

I had hoped to just buy a new electrical unit as the mechanical part of the latch is perfect. However, you have to buy a complete latch and electrics which is a shame. A replacement 2nd hand part from EBay may suffer from the same problems long term. 

Hope this helps someone in the  future

[Breezy_Pete]

Nice work figuring out what's what.  If you remove the microswitches is there enough info printed on them to ID them with a view to individual replacement?

[prt57]

I have bitten the bullet and ordered a complete new unit for peace of mind.

Shame really as the mechanical components were fine. As this appears to be a fairly common problem you would have hoped Skoda would have just sold the part that breaks, especially in these times when waste is to be avoided. However, the metal lever that actuates the nylon cam had worn a groove so in time there may be other issues if the full movement was compromised. 

[Breezy_Pete]

What part number is the bit you've ordered, please? (the boot light on my missus's car is very 'hit and miss').

[TMB]

The switch with the green wire also tells the system that the tailgate is open/closed.

Edited 29 December, 2020 by TMB

[prt57]

1 hour ago, TMB said:

The switch with the green wire also tells the system that the tailgate is open/closed.

All the guy needed to do was to disconnect the wires to the switch. No boot light and no warning on the dash. 

[Breezy_Pete]

I'm 99% certain that wouldn't have been an MOT failure either.

[prt57]

1 hour ago, Wino said:

What part number is the bit you've ordered, please? (the boot light on my missus's car is very 'hit and miss').

I’ll have a look at my existing part in the morning as the replacement had the same reference. 

The number is stamped on the orange latch component on the metal just near where it sits in the tailgate. Imagine sitting on the inside of the tailgate then look up to the latch. 

[prt57]

Sorry about the delay in posting the part numbers. 

The replacement part number for my car which has central locking is shown on the plastic wrapping, same as the part number on the original component. It is a nuisance to have to buy the whole latch and micro switch gear when there was nothing wrong with the metal parts but at least I got a bit of discount. 

The reason why the boot light micro switch breaks is that if you look at my earlier photo you will see the switch near the green wire has a sprung piece of metal that pushes directly down onto the micro switch whereas for the micro switch that goes wrong, the cam rotates and pushes the micro switch down but also to the side slightly. Over time this is what causes the wear. A poor design in my opinion. 

New latch installed and perfect operation. 

[Breezy_Pete]

Part number seems to vary between estate and hatchback. And pre/post facelift I think, so best to check what's on ones own car before acquiring replacement.  

 

Any chance of having a closer look at the duff microswitch in search of part numbers? (might be on other side).

 

[prt57]

Here you go Wino. 

Both micro switches are made by Cherry. The dodgy switch terminals are labelled 1,4,2 leading from the microswitch end. 

The only other reference is 

4A

24 

in this arrangement on the side of the housing with the switch. 

 

I had managed to get the dodgy switch working again with contact cleaner but not 100% reliably so no good.

 You may find that the orange dust shield grommet has come forward towards the end of the plunger as mine had this reducing full movement. I pushed it back and full movement was restored with encouraging click sounds but as mentioned, not totally reliable. 

[Breezy_Pete]

Nice one, much appreciated.  I'll see what I can find.

[TMB]

4 hours ago, prt57 said:

whereas for the micro switch that goes wrong, the cam rotates and pushes the micro switch down but also to the side slightly. Over time this is what causes the wear. A poor design in my opinion. 

 

It's the same with the door microswitches. The latch moves sideways across the plastic microswitch button and acts like a file, eventually wearing the button away. Rubbish design.

[prt57]

Yes I encountered the door micro switches on my Mk 4 Gti. I had trouble with the interior lights again and then the rear locks started playing up. I had to replace all 4 locks. Dreading it happening on the Fabia as my car has the riveted metal door card rather than the bolts on the Golf. What a mental way to do things.

I had to remove the front passenger door card to fit a new window mechanism on the Fabia and knackered my hand trying to operate the manual rivet gun as sold by Halfords when reassembling. 

Any recommendations for a user friendly rivet gun that won’t ruin my knuckles squeezing the arms together?

Edited 31 December, 2020 by prt57

[TMB]

22 minutes ago, prt57 said:

Dreading it happening on the Fabia as my car has the riveted metal door card rather than the bolts on the Golf. What a mental way to do things.

 

Yeah, it's a pain. I'm lucky in that mine are bolted as they used bolts until about 2003.

 

24 minutes ago, prt57 said:

Any recommendations for a user friendly rivet gun that won’t ruin my knuckles squeezing the arms together?

 

A lazy tongs riveter is what most use.

[sepulchrave]

I can recommend a cheap air riveter if you have access to a compressor, awesome and cheaper than lazy tongs.

[Breezy_Pete]

@prt57 I finally got round to sorting this on the Fabia, and this info from you was super-helpful, so thanks again.

 

I initially bought a spare catch from ebay with the idea of researching replacement microswitches with the original catch on the bench, hoping the replacement catch would work at least for a while.

I bought a suffix M part which turned out to be a mistake, as that appears to be a pared down version to suit a car without boot light; so no microswitch in the relevant position! Oops... 😆

 

Then I got to measuring the spot it fits in, and trying to figure out what would go there.  Eventually settled on a DJ1G-AG29 which I ordered from Aliexpress.  It fits, it appears to work, though I'll give it a few weeks in service before being really confident o fits reliability.  It's even marked Cherry, but with slightly different other markings from the one you photographed upthread, and the one I've just found in the original latch, these new ones have A5 31 written on instead of the A4 27 on ours, and 4A 24 on yours.  Can't get too excited about trying to work out what these mean, one pair of digits is probably a date-code.

 

I lubed the cam that actuates it with a bit of grease, to help things along. It's really a straightforward repair; hardest part is getting the bloody boot trim panel back on right, that's just horrible with all those trim clips and not really able to see.  Don't forget to pass the little fabric loop through the slot either, if you ever use it to pull the tailgate down. 

 

Anyhow, I'll 're-microswitch' the now spare original latch  (6Y0 827 601H) and make it available to anyone who wants a fixed one, maybe with an exchange price option as I bought a few spare switches with that in mind. Have you kept your old one @prt57? I'd be glad to send you a microswitch FOC if you wanted it.

 

 

 

 

 

 

 

[prt57]

2 hours ago, Wino said:

@prt57 I finally got round to sorting this on the Fabia, and this info from you was super-helpful, so thanks again.

 

I initially bought a spare catch from ebay with the idea of researching replacement microswitches with the original catch on the bench, hoping the replacement catch would work at least for a while.

I bought a suffix M part which turned out to be a mistake, as that appears to be a pared down version to suit a car without boot light; so no microswitch in the relevant position! Oops... 😆

 

Then I got to measuring the spot it fits in, and trying to figure out what would go there.  Eventually settled on a DJ1G-AG29 which I ordered from Aliexpress.  It fits, it appears to work, though I'll give it a few weeks in service before being really confident o fits reliability.  It's even marked Cherry, but with slightly different other markings from the one you photographed upthread, and the one I've just found in the original latch, these new ones have A5 31 written on instead of the A4 27 on ours, and 4A 24 on yours.  Can't get too excited about trying to work out what these mean, one pair of digits is probably a date-code.

 

I lubed the cam that actuates it with a bit of grease, to help things along. It's really a straightforward repair; hardest part is getting the bloody boot trim panel back on right, that's just horrible with all those trim clips and not really able to see.  Don't forget to pass the little fabric loop through the slot either, if you ever use it to pull the tailgate down. 

 

Anyhow, I'll 're-microswitch' the now spare original latch  (6Y0 827 601H) and make it available to anyone who wants a fixed one, maybe with an exchange price option as I bought a few spare switches with that in mind. Have you kept your old one @prt57? I'd be glad to send you a microswitch FOC if you wanted it.

 

 

 

 

 

 

 

Hi Wino, 

Thank you for your thanks!!

I cannot believe I was tackling this over a year ago. Time flies and apart from the dodgy refurbished steering rack episode and a replacement alternator everything has been OK in my “Elegance” since. 

Thank you for your offer of a spare micro switch but for me, it something does not work and I’m unlikely to need it, the component goes in the bin!!

[Breezy_Pete]

A deeper dive into the microswitch in the latch that came off our 175k mile car on Saturday suggests it's an electrical contact failure rather than a mechanical/wear issue with the microswitch mechanicals.

Comparison of the 'on' resistance of new and old microswitches (with a cheap multimeter):

New - less than 0.2 Ohms

Old - around 8 Ohms

 

Teardown revealed a really tiny contact patch between moving and static parts, with a sooty and uneven/worn surface on both sides.  Easier to see (with a microscope) than to photograph, but here's a best effort at it. The goldy coloured bar is the moving contact, the round blackened patch visible on the more silvery static contact.

 

So nothing to be gained by cleaning and re-lubing the microswitch/cam externally, in my opinion.

[Tailhappy]

Just waking up this topic - does anyone have the link to suitable switches used as I would like to fit new ones to sort out the boot light (always been a bit flaky). I would order the complete assembly but it seems to be only available used at a steep price...and no guarantee of working.

[Breezy_Pete]

I have a bag of switches and a refurbed latch available, see posts above. PM me. 

[Jcb.]

Sorry if this is off topic, unsure if it’s related...

 

Would this same issue be the cause of the boot not opening from the rubber button on the tailgate, but it will reliably open off the remote key (middle button)?

[prt57]

I would say not related as the tailgate boot rubber handle has a switch in it. 

[TMB]

10 hours ago, Jcb. said:

Sorry if this is off topic, unsure if it’s related...

 

Would this same issue be the cause of the boot not opening from the rubber button on the tailgate, but it will reliably open off the remote key (middle button)?

 

Try opening one of the rear doors first and then try the rubber button. If it opens it suggests driver door microswitch malfunction.