Technical Identification of wiring and connection of the FIAT 500C 2014 light switch

[grro7201060]

Good morning everyone......
I would like to install a universal kit for turning on the low beam headlights via a light sensor.
In addition, I would like to point out that this kit works in all logics, both positive and negative.
The problem is that now I can't find any signal coming from the light switch.
I tried to disconnect the wiring under the steering with the hope of finding the two pins that would provide me with a closure/opening when activating the light switch but I found nothing!
Can anyone help me on this?
Thank you so much in advance

 

[John202020]

Simplest option just leave the lights
on? Will come on with the key.
Lights are can bus operated, there's a risk changing anything

 

[grro7201060]

John, Thank you first of all for your reply.
i saw that you have the wiring diagram. unfortunately i couldn't find it anywhere.
Could you be so kind as to post the diagram so i can look up the colour of the wires that go to the headlights and are at the body computer output?
I understand that there are no relays in between, right ?
Cheers

 

[steveras57]

Hi have to say im with John on this one!
Fiats can-bus system is "touchy" and sometimes can react badly to changes that put values outside of expected parameters, leading to issues with other systems that you have not touched! ,they often go wrong without any help from us let alone adding a feature the car was not designed to have! tread carefully here! you dont want to cause yourself any unexpected problems!.

 

[John202020]

It looks like at the stalk switch it's either 6+2 or 5+2 for switching options, pull the plug on the stalk and see which pins( on the stalk) go closed when you turn to headlights on? It's these two that your auto switch would parallel switch via a small relay?
Note if you do try this, you could have a problem when flashing someone or switching to main beam as the auto switch would hold the standard on signal whereas the stalk would have changeover?

 

[John202020]

My ultimate suggestion is, headlights on all the time, ie on, auto switch holds the headlights off ( by two relays near lights ) and the turns them on when dark? Kind of the opposite, so only side lights on all the time, also means the drl always off though, this also means the canbus/original set up bar close to lights is unaffected

 

[decappottabile]

Maybe it helps if you can explain why you want to do this? As mentioned, it's much easier and free to just leave the lights on.
Personally I never rely on the light sensor in any car. Either they switch the lights on too early, too late, or not at all, for example in foggy conditions.

 

[grro7201060]

My ultimate suggestion is, headlights on all the time, ie on, auto switch holds the headlights off ( by two relays near lights ) and the turns them on when dark? Kind of the opposite, so only side lights on all the time, also means the drl always off though, this also means the canbus/original set up bar close to lights is unaffected

Thank you all for the suggestions, at this point I could run wires directly to the headlights, you have to figure out which wires go directly to the low beam headlights from the bodycomputer but the same thing has to be done for the tail lights and licence plate lights. As far as the reliability of the kit is concerned, you can override it whenever you want via a switch on the sensor.

 

[steveras57]

I have a light sensor fitted to mine! its called my BRAIN!

 

[grro7201060]

I have a light sensor fitted to mine! its called my BRAIN!

not my daughter .... ahahahah

 

[steveras57]

not my daughter .... ahahahah

wouldnt let her drive the car then !!

 

[grro7201060]

Simplest option just leave the lights
on? Will come on with the key.
Lights are can bus operated, there's a risk changing anything

Hi John would you be so kind as to tell me where the connector for the lever connections on the steering wheel is?
I would like to try to see if switching on the headlights from the headlight devioluce (left lever) I find a ground that closes.
Thanks

 

[jackwhoo]

Hi,

Do not use the kit you have bought .
It has a warning "if lights manually turned on - make sure to turn the lights off before turning the ignition off "

It doesn't explain what will go wrong if you don't manually turn the lights off before turning the ignition off!!!! Total melt down?

As lots of others have suggested leave the light switch in the on position - safer for your daughter and everyone around her.

Best wishes
Jack

 

[grro7201060]

It looks like at the stalk switch it's either 6+2 or 5+2 for switching options, pull the plug on the stalk and see which pins( on the stalk) go closed when you turn to headlights on? It's these two that your auto switch would parallel switch via a small relay?
Note if you do try this, you could have a problem when flashing someone or switching to main beam as the auto switch would hold the standard on signal whereas the stalk would have changeover?

Dear John.....I found a way to solve the problem .... of course then I will post it!
Before I start testing the circuit, however, I need to understand how the tail lights and number plate lights are connected.
Would you be so kind as to post the diagram if you have it?
Thank you very much in advance
RG

 

[John202020]

Dear John.....I found a way to solve the problem .... of course then I will post it!
Before I start testing the circuit, however, I need to understand how the tail lights and number plate lights are connected.
Would you be so kind as to post the diagram if you have it?
Thank you very much in advance
RG

I'll try and out it tomorrow

 

[grro7201060]

I'll try and out it tomorrow

Thank you so much John!

 

[John202020]

Hope this helps been out today

 

[grro7201060]

Good morning everyone, I am writing to let you all know that I have installed the universal lighting kit.
Below I will explain how I connected it in consideration of all your attention to the body computer signal issue.
- I used the kit configuration to provide a ground signal (negative concept);
- I provided the ground signal to pin 6 of the headlight ignition lever assembly;
- I powered the kit with the positive under the key.

Everything is fully functional and no malfunctions have occurred. I want to thank everyone especially John who provided me with the wiring diagrams.
I remain at your disposal for any questions