C5 X7 2016 additional lightbar installation problems

[Oudii]

The purpose is to put an additional light panel in my car. Everything needed has been acquired: CAN relay, wiring harness, bracket, bandit connectors, plate connectors, pliers, etc. Information has been dug up here as well as from other forums and the internet. There seemed to be very little previous experience from people about installing additional lights in the C5.

Everything was planned to go well from start to finish. However, this rarely happens. The problem turned out to be that I can't find out from the OBD port to which different wires I should put the t-shaped bandit connectors. CAN-HI and CAN-LO come from the CAN relay, and the car's CAN bus also has its own HI and LO wires where these should be connected. As a guide, I had received that these HI and LO wires come from pins 6 and 14 of the OBD port.

So I took it upon myself to remove the protections from the center console in order to expose the OBD port. With the strip tool I lifted the plastics off the console and tried to remove the plastic around the OBD port. For a few hours I watched and tried my best, but to no avail. It didn't help that the wires were dimensioned in such a way that I could only pull the plastic strip five centimeters outwards. It was absolutely impossible to see the wires coming from the pins, I tried to use the phone's camera to help, but I couldn't get the picture to be focused enough to do anything with it.

So the question is: is there any way to get the OBD port out of that plastic strip? The only way I could figure this out in my opinion. Does anyone have experience with putting additional lights in a C5 yourself with a CAN relay?

I included pictures just to be sure.

Thanks for the answers in advance!

[wheeler]

Not sure what you mean by light panel. Is it an external light bar or something? If so your setup seems a bit overkill.

[Oudii]

Its extra headlight. I live in Finland so many of us have some kinda extra lights or bar/panel under or top of the license plate.

[Jay-Bruce]

Going for a CAN-Bus relay is a very high tech, and elegant solution, but it maybe overkill for this applicaiton? In Land Rovers I've put a spur off of the wire going to the headlight bulb holder as a signal for a relay to control a fused spur to the light bar / spotlights, perhaps a simple "hack" like that could be suitable for putting your light bar?

Although, for all I'm explaining the "simple" solution, I'd love to follow a thread on how you go about this, I'm genuinely curious how, after tapping into canbus, you set up the relay to decode all the chatter and set it to respont to a certain status update, such as "relay on when headlights go full beam" or whatever...

[Sloppysod]

A big problem with the X7, possibly others as well, is getting wires from cabin to the outside, so sending a signal through the Canbus network would probably be a good idea, and interesting, I will be watching and learning to.....
Good luck

[Oudii]

Installation through CANbus, finnish subtitles only.


In this video you can see mechanic working on Benz ja the Canbus network going throught the passengers feet area, it was same in the my C5. I could see through the plastic covers caps that there was the same kinda wire set.

The installation seems pretty straight forward and simple but problem is how i can know the right cables if i dont see the other side of the OBD port.

I'll try to updste if get some progress on this thing

[wheeler]

It really depends how you want to control this lamp? do you want it on an independent switch or do you want it to come on with say the front foglamps?
If this was the case i would just use the fog lamp signal at the under bonnet fuse box to pilot a relay to switch it on. It could easily be done nice and neat this way.
That being said im also curious about this CAN relay, do you have a link to the device you are using, id like to get a look at the spec & possibly a wiring diagram.

A big problem with the X7, possibly others as well, is getting wires from cabin to the outside, so sending a signal through the Canbus network would probably be a good idea, and interesting, I will be watching and learning to.....
Good luck

All C5's Have 4 'repair' wires that are already part of the harness & run from behind the BSI & exit in the under bonnet fusebox, These can be used for either repairing & bypassing damaged wires or installing accessories. These could be used for this as they are already part of the harness that goes from inside the cabin to the engine bay.

[Oudii]

I'm talking about this same thing in finnish Citroen forum and they are suggesting the same thing that you are. Take the signal from high beam fuse with fuse splitter and connect the excitation signal cable from the led bar to the splitter. Then i should not need the CAN relay. Only thing i'm worrying about is that automatic system in the car will detect too much power going to the headlights as i put the led bar on and shut it off completely. In the finnish forum they sre saying the relay wont take too much power at all and all should be good.

[Oudii]

Here is the relays details:
https://www.canm8.com/can-bus-interface ... hbeam.html

[wheeler]

The relay itself will only draw a few milliamps from the fog lamp or high beam circuit . The actual power supply should be a fused feed from the battery.

[wheeler]

So just had a look at the CAN box thing. I’d say definitely overkill for what you want to do as you will still need to fit a relay anyway as the unit has a max output of 1 amp. In fact using this will require more wiring than if just using a normal relay.

[Oudii]

So what is the point in the relay? Most of the mechanic who do these kinda extra light installations on cars here say to use it. Makes no sense.

[Steve Walsh]

The relay in the circuit is operated with a small current from the switch, to send a high current to the lights.

[Oudii]

Sorry my bad, i mean the CAN relay?

[Paul-R]

Perhaps if you think of it as an interface which can supply a low power supply when triggered by an event (main beam). The supply is only enough to power a low power device and the "normal" relay is needed to provide power to auxiliary lights.