Im looking specifically for the ones regarding the rear lighting and where to get a 12v power supply in the boot area.

I really am in desperate need of the wiring diagrams of the rear lights of my car, as I need to install a towbar.

Official source is: https://erwin.skoda-auto.cz/erwin/showHome.do 

21 minutes ago, langers2k said:

Official source is: https://erwin.skoda-auto.cz/erwin/showHome.do 

Is that the only way to get what I need?

I have never needed a wiring diagram to wire up towbar electrics, I use my eyes and a voltmeter.

 

The accessory socket in the boot area is the most convenient location for the 12v feed for the relay.

11 hours ago, lotrjw said:

Is that the only way to get what I need?

 

Nope but probably the easiest.

 

You might be able to find Elsawin somewhere but as it's pirated software it may be riddled with bugs and viruses...

2 hours ago, langers2k said:

 

Nope but probably the easiest.

 

You might be able to find Elsawin somewhere but as it's pirated software it may be riddled with bugs and viruses...

Is their a haynes that covers it? I know there is a diesel one, but perhaps that will give me the wiring I need for the rear lights? 

12 hours ago, J.R. said:

I have never needed a wiring diagram to wire up towbar electrics, I use my eyes and a voltmeter.

 

The accessory socket in the boot area is the most convenient location for the 12v feed for the relay.

Thanks I might have to just go with that.

Just be wary of the brake and fog lights.

 

If I remember correctly, despite using dual filament 21/4W bulbs, you may find it only uses the 21W filament for both brake/fog and tail lights. It uses PWM to dim the 21W filament to the right brightness for the tail lights rather than using the 4W filament.

 

If you're using a bypass/relay box style towing electronics, this may confuse it.

1 hour ago, langers2k said:

Just be wary of the brake and fog lights.

 

If I remember correctly, despite using dual filament 21/4W bulbs, you may find it only uses the 21W filament for both brake/fog and tail lights. It uses PWM to dim the 21W filament to the right brightness for the tail lights rather than using the 4W filament.

 

If you're using a bypass/relay box style towing electronics, this may confuse it.

Ah so what would be the best thing to do in that instance?

2 hours ago, langers2k said:

Just be wary of the brake and fog lights.

 

If I remember correctly, despite using dual filament 21/4W bulbs, you may find it only uses the 21W filament for both brake/fog and tail lights. It uses PWM to dim the 21W filament to the right brightness for the tail lights rather than using the 4W filament.

 

If you're using a bypass/relay box style towing electronics, this may confuse it.

 

If you use a multi-meter to test which wire has voltage when each light is activated it would soon be apparent were it to be as you say.

 

I have fitted/refitted towing electric relays to a 2006 Octavia and a 2015 Yeti and the wiring was standard old school, I have my doubts about your theory because were it true when the rear lights & fog lights are on the brake light would only show on one side which I dont think would meet the vehicle C&U regulations.

 

Also the rear fog light could not be distinguished from a rear light fault, bulb incorrectly inserted for instance.

Edited 10 January, 20215 yr by J.R.

30 minutes ago, J.R. said:

I have my doubts about your theory because were it true when the rear lights & fog lights are on the brake light would only show on one side which I dont think would meet the vehicle C&U regulations.

 

I think you've misunderstood me?

 

There are two 21/4w bulbs and two W3W used to create the C-shape tail lights in each rear cluster on a MK2 Octavia:

- All four are lit as tail lights to give the C-shape

- The top most 21/4W bulb gets brighter for brakes

- The bottom most 21/4W bulb gets brighter for fogs

 

That behaviour doesn't change, it's the method to achieve it that does.

 

Note: Obviously there are two more 21W bulbs for reverse and indicator but that's unrelated to my point.

 

It would be logical to assume the tail lights would use the two W3W and the two lower powered 4W filaments from the dual filament bulbs. I believe some earlier cars did use this method.

 

Yet plenty of Octavia's use the two W3W and the two higher powered 21W filaments to create the C-shape. The car's BCM uses PWM to under drive the 21W filament to lower their brightness so they match the W3W bulbs. When either the brake or fog light is needed, it changes the duty cycle to increase the brightness

 

An example would be my old MY12 Octavia hatch, on the connector to each rear cluster, there were only 5 wires despite the plug and socket having 6 positions:

- ground

- indicator

- reverse

- top/brake 21W filament

- bottom/fog 21W filament

- empty

 

Despite this, I still had the full C-shape on both sides. The 6th position did have a track on the light cluster to the top/bottom 4W filaments but it had no wire and was unused.

 

I can only imagine it was done to make bulb monitoring easier...?

 

Is this setup consistent for the whole O2 range or perhaps from FL onwards?

4 minutes ago, StickyMicky said:

Is this setup consistent for the whole O2 range or perhaps from FL onwards?

 

Honestly no idea. It seems like the hatch and estate may also use difference schemes . At least based on a post from previous me (who'd believe that guy!? ) it seems that the estate may use a 21W rather than 21/4W so it has to use a PWM method to get the full C-shape.

 

Easiest way to check is to remove the bulb holder, put some sunglasses on and ask an assistant to try the tail/brake lights. You should be able to see if the same filament is being used or if it swaps

 

 

Apologies Langers, not only did I misunderstand you I had not realised it was you that had posted the info, as one of my trusted and highly regarded sources I would not have doubted it had I realised

 

Nonetheless the two vehicles I spoke of with 9 years between them both had old school wiring, the set up you describe would indeed cause problems for the sensing module

Update.

So I fitted the bar today, that was a job and was strange in that you have to remove the rear crash bar to actually to fix it in, but thats what the instructions said so thats what I did.
The electrics are quite confusing, I found a 12v supply in the back but quickly realised its the supply for the parking sensors and had to find another!

I attached the 7 cables for the lights to what I thought they would be, but  something isnt quite right. The tails work, I think the stop lights work, but no fogs or indicators so I must have something off. Anyway its too late for today and the car lights arent effected, as would be expected, so I will try another day. Im about half way there and I have more cable to get the 12v supply straight from the battery or fuse box, so I shouldnt need the low amp one in the boot. 

Update:

OK so I found this: 
Something that didnt come with any of the bits I brought, which says if there is common brake/tail and or fog/tail then dont connect the brown and black tails. My Skoda seems to have both somehow? It seems to be like langers2k said his old car was in his post in this thread. 
So I missed out the two tail leads and  have break and tails working OK. Unfortunately the Fog still doesnt work, but I got the indicators working. There is no reverse lights on my trailer but I checked the pin that should be for reverse and I got nothing when I use a meter to earth/ground. I get 12v on the two pins that are supposed to be live for internal caravan electrics so thats all good. 

Does anyone have any idea why my Fog and Reverse lights arent working and how I might fix them?

I can use the trailer when there isnt Fog, but really want it sorted as its obviously a legal requirement to have a working rear fog light.

On 10/01/2021 at 01:10, J.R. said:

I have never needed a wiring diagram to wire up towbar electrics….

its not 12 volt. Same problem with my Scala. Meter is useless 

22 hours ago, BenScala said:

its not 12 volt.

It sure is!!!

 

Had to fiddle with mine yet again before setting out on a 1000 mile towing round trip, 12v it certainly is both the power to the relay, the outputs and the sensing currents.