I know this might have already been posted but Im new to the website and not sure how to use it yet and put a post in wrong forum already -.-! so i think this is right one but anyway here's my issue with my interior light.

The interior light was intermittent there is a aftermarket sunroof fitted (Topline) what started to leak and couldn't get a seal so sealed it shut and wanted to disconnect sunroof power so i took interior light out and checked and the sunroof was connected to interior light so i disconnected and now the interiorlight has stopped working all together!. Talking to electrician at work he seems to think its relay that's had too much current put through it and thats the problem but my problem is where is relay? and which relay is it that controls light? Fuse is also fine.

Please help.

 

Many thanks joe

If your electrician colleague is correct, and fuse 4 has been replaced already, this presents you with some difficulty.  There is a relay that controls all the interior lighting (do the glovebox light or boot light work, or not?), but it's part of/soldered into a module known as the 'electrical system control unit' which lives just below the location of the plug-in relays, roughly behind the light switch. Haynes wiring diagram 5 is my source of info for this.  It would be relatively straightforward to identify which relay on the circuit board is the relevant one, and de-solder/replace, but it's not a ten-minute job unfortunately. Alternatively, A.N. other module could be sourced and fitted, but that might well need coding to the car, not sure. 

 

I see that the factory sunroof installation uses a 25A fuse (Haynes wiring diagram 9), so whoever thought it would be fine to power a sunroof from something fused at 10A needs a bit of a talking to.

Thanks for your reply, no the boot light is also dead and the glove box does not have a light also i checked the voltage coming through the interior light and its only showing 9v even when cars running it stays the same i checked the cables going to the pillow at the passenger side of the car and its all in good condition so no sign of bunt cable. 

I do agree that the prats who put the roof in Auto roofs at leicester uk made a poor job of connecting the roof but they did this some 12 years ago so cant really go back.

Do you have any pictures of the electrical system control unit? so i know what to look for and what relay this is?.

 

Many thanks joe

Here's an ebay listing with a  photo of the whole thing (but part number may not be exactly right for your car, so don't just buy that). It sits horizontally in the car with those connectors facing downwards, with a mass of loom wiring hanging out.

 

Here's a close-up of the relay that seems to do the interior lights, hopefully with part number clear enough.  Haven't looked (have now, can be had) to see whether it can be bought easily.  I do note that it has ten pins soldered into/through the board, so would need someone reasonably skilled to extract it without damage to the board.

 

Hi, brilliant thank you so much for your time i will look into this and see what i can do.

 

many thanks joe.

Shame you're not nearer or I'd offer to have a go at the de-soldering/replacement for you.  If you could be without the car for a few days I guess you could post it (the control module, not the car  ) (and new relay) to me? I work in electronics so I'd have a fair amount of confidence that I wouldn't bugger it up.

Hi, thanks for that offer i think im going to have an attempt of taking this off the car not sure how it all come apart yet to get to it then i think im going to go for the option of a another working used unit and just connect it then have old one repaired by the electrician  at work and sell the repaired part.

 

many thanks joe

This thread has info on how to remove the lower dash panel on the driver's side, which gives access to the area.  I'm not sure how hard/easy it is to extract the module, because I've never tried. At least from looking at the module I have here, all the connectors are differently keyed, so that they will only plug into their correct places.

Hi, brilliant thank you so much for you help.

your a massive credit to this site.

 

Thank you again 

 

Joe

Apologies for hijacking this thread, but did this work?

 

We have just bought a 2007 Fabia 1.9 tdi and none of the interior lights work on that. 

 

Also the speedo and dash illumination doesn't work. Do your dashboard lights work? Or is this all part and parcel of the same fault? The symbol lights work, just the overall illumination that you'd expect to come on when the headlights are turned on.

 

We've checked all the fuses and they are fine.

 

If the relay is to blame then I can go ahead and purchase one of those on the link above and then solder it in (many years spent making PCB's as a student will suddenly pay off)!!!

I don't think the lighting of the clocks is on the same circuit, but I could be wrong and I'm too tired to check just now.

One thing to check though; you know there's a thumb-wheel dimmer thing just to the right of the rotary sidelight/headlight switch? That might have got knocked round to a very dim setting.

Thank you! 

 

No, it's definitely not the dimmer switch (at least, not that it's set to dim). That's the first thing I asked. Personally I think it's a separate issue and looking into it a bit this evening online, it looks like there is something within the dimmer switch itself which goes wrong, so options there (assuming that's where the fault lay) seem to be to get a new dimmer assy, or link across pads on the board to effectively take out the dimmer facility so the lights are set to 'bright' permanently. Having looked into this, the dash illumination seems to be the easier of the two problems!

 

Regarding the interior lights, is it safe to assume that the relay is the only culprit, having ruled out the fuses? What I'm asking I suppose, is if it's just worth going ahead and getting the relay that you identified above, the one from Poland, via ebay and just swapping it out, or could there be other culprits that I should look at first?

I'll stick up a snapshot of the relevant bit of a wiring diagram later when I escape the gravitational pull of this bed...

Other possibilities that spring to mind:

The connector (XP2) that takes 12v in and out of that relay is disconnected from the module (unlikely unless 'tampered with' as I imagine they are securely latched).

All bulbs blown (also seems far-fetched).

The various switches aren't working.

Broken wire bringing 12v into or out of the loom connector that plugs into module.

 

Owing to the slightly involved nature of removing the module to get at the relay, it would make sense to systematically rule out as many as possible of the above first. (And the ones I haven't thought of!).

 

Here you go, I think this diagram is appropriate for cars with central locking. One possibility that I didn't think of earlier is that the brown/yellow (br/ge) wire from connector XP4 of the module at the top of the diagram could cause the interior and door lights not to work if it was broken, but the reading lights would still work if the switch was moved to that position, because they have a permanent ground on the brown wire, bottom right in the diagram.  Main thing to check really is what voltage you see on the red/black (ro/sw) wire coming out of XP2 pin 6, which is almost certainly easier to investigate at pin 2 of the 3-pin connector of the interior light "W".

 

You absolute star. THANK-YOU!

 

I'll print all of this off for hubby. He's an electrical designer, so will have no problems with this and all of the diagnostics you are suggesting.

 

I'll come back and report on the outcome. 

 

Fingers crossed it's something simple... (like that's ever the case...)

 

Again - thank you. Your assistance with this is very much appreciated!

Hello, this is Sally007's husband. Thanks very much for your previous advice on Skoda Fabia interior light fault. I have removed the interior light and measured the voltage at the ro/sw (red/black) cable (coming out of XP2 pin 6) feeding the interior light and 0v is present. I suspect the relay coil itself is not being energised as I have sat in my wife's car (Audi A4) and locked/unlocked the car whilst sitting inside and observing the interior light behaviour. When you lock the car about 5 seconds later you hear the interior light relay switch off and the interior light goes out (even in the permanently on position). I would expect the Fabia to behave in the same way but there is no click heard on locking the car whilst sitting inside.

On an additional note the glovebox and boot lights are not working either (I have tested all 5 bulbs as a long shot and they all work on a 9v battery).

The previous post my wife regarding the instrument lights was indeed a red herring as this all works fine. I turned up the small rotary thumb rheostat adjacent to the road light switch and the dash glows green so I can at least see the speedo at night !

I spoke to a Skoda person at a garage today and they have suggested plugging in their diagnostics computer for £60 to see what could be wrong. I have not done this yet and would suspect that "no fault found" will be the computers response !

It is a shame as it is such a lovely little car in all other areas.

Needs a new comfort module by the sounds of it. You could get a used one off ebay fairly cheaply.

Hello, this is Sally007's husband. Thanks very much for your previous advice on Skoda Fabia interior light fault. I have removed the interior light and measured the voltage at the ro/sw (red/black) cable (coming out of XP2 pin 6) feeding the interior light and 0v is present. I suspect the relay coil itself is not being energised as I have sat in my wife's car (Audi A4) and locked/unlocked the car whilst sitting inside and observing the interior light behaviour. When you lock the car about 5 seconds later you hear the interior light relay switch off and the interior light goes out (even in the permanently on position). I would expect the Fabia to behave in the same way but there is no click heard on locking the car whilst sitting inside.

On an additional note the glovebox and boot lights are not working either (I have tested all 5 bulbs as a long shot and they all work on a 9v battery).

The previous post my wife regarding the instrument lights was indeed a red herring as this all works fine. I turned up the small rotary thumb rheostat adjacent to the road light switch and the dash glows green so I can at least see the speedo at night !

I spoke to a Skoda person at a garage today and they have suggested plugging in their diagnostics computer for £60 to see what could be wrong. I have not done this yet and would suspect that "no fault found" will be the computers response !

It is a shame as it is such a lovely little car in all other areas.

Not hearing the relay click is a good observation, but that could either be because the coil has failed or because it isn't being driven for some reason; so it still could be just the relay, or it could be 'deeper'.

I suggest you have a look at VCDS (a DIY diagnostics system: there's a section devoted to it further down the main page). There may be someone near you willing to connect up your car for a diagnostic scan for something more like a bottle of wine, rather than £60. If you ever come near Abingdon in Oxon, I'd be happy to try, but there ought to be lots of nearer Briskodians with the facility to help.

Thankyou very much.

I will look at the diy diagnostics route.

hi as this been solved? as i have same problem

Hi, yes I have resolved my issue was the small 10amp fuse turned out it blew in such a way it still made contact every now and then. I looked into replacing the relay before I found the fuse was faulty and to replace the relay ain't a 5 minute job and will take someone with a good steady hand to un solder and then re solder a new replacement relay. What yoy should do is check fuse number 4 the small red 10amp if this is working turn the light on and remove the fuse and listen to see if you can hear the relay click then your problem is else where.