Citroen c5 X7 Xenon headlight retrofit on steel sunspension

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Dzony97
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Citroen c5 X7 Xenon headlight retrofit on steel sunspension

Unread post by Dzony97 »

Hello

For some time, I was looking for a way to retrofit xenon headlights to my C5 X7.
I know everyone is saying that it is impossible, even with a hydroactive suspension, but I found a few diagrams that prove it can be done. For someone who is an auto electrician, wiring is not a problem, and that part is already done.
Things I've done till now are:
Installed LED DRL xenon headlights
Changed pinout for headlights
Installed headlights washers
Installed Height sensors on front and rear axle.
Installed Headlights ECU.
And coded everything using diagbox.
Problems that I'm facing now are:
Headlights ECU can be reprogrammed to Steel suspension after that ECU is requesting both front and rear height sensors
Even though they are connected and installed properly, I am getting a fault for an open circuit of them.
And the rear Height sensor is reading an invalid value in Parameter measurements
The front one is also not changing % when moving it, but at least it is reading something from it.
Vehicle speed is always stuck at 050 kph even though the vehicle is standing still.
The faults that I have are:
B1111: Vehicle height sensors not programmed
C1147: Rear vehicle height sensor signal
C1142: Front vehicle sensor signal
Corresponding to these faults, headlights went into some let's call it safe mode, and are lowered all the way, plus the directional movement is not working.
After some looking for parts and other things I found out there are a few different numbers for the headlight auto-adjustment unit, and they are:
6224P4, 6224 P5 and 6224T4.
My question is :
Since I took all the parts, headlights, and auto adjustment unit + height sensors from a car that had hydroacitive, could it be possible that even though ECU is reconfigurable that it does nothing to it, since on the connector for leveling ECU I didn't have wires for leveling height sensors I just used diagram and added pins to a connector to be more precise (B2, C1, C2 and C3) Pins.
But still get these errors and can't program height sensors.
Could there be a possibility that I would need to find a Leveling ECU from a car that came with springs and not hydroactive to make it work? Since everything else is working as it should.

Best Regards
N.M
Kees
Donor 2024
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Re: Citroen c5 X7 Xenon headlight retrofit on steel sunspension

Unread post by Kees »

Dit you also mount the body height sensor at the rear of the car?
This one is used for correction of the carrosserie position.
You only mentioned the height sensors at the axels.
Dzony97
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Re: Citroen c5 X7 Xenon headlight retrofit on steel sunspension

Unread post by Dzony97 »

I installed these two. By the diagram that I got, there are only two sensors: front and rear on a non-hydroactive suspension. On hydroactive, the headlights ECU takes information by CAN bus from the hydraulic ECU.
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Kees
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Re: Citroen c5 X7 Xenon headlight retrofit on steel sunspension

Unread post by Kees »

20250702_113259.jpg
This is what I mean, I think you call it, proximity sensor.
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Dzony97
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Re: Citroen c5 X7 Xenon headlight retrofit on steel sunspension

Unread post by Dzony97 »

Hmm i didn't fit that one,but its not even visible on a diagram, i will post a diagram later, maybe im missing something, or maybe that one is only available on hydroactive suspension .
Kees
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Re: Citroen c5 X7 Xenon headlight retrofit on steel sunspension

Unread post by Kees »

I try to find it on the service box, but couldn't find it.
vallium
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Re: Citroen c5 X7 Xenon headlight retrofit on steel sunspension

Unread post by vallium »

Kees wrote: 02 Jul 2025, 10:42This is what I mean, I think you call it, proximity sensor.
Image
Image
I believe this triangular thing is antenna for TPMS
Kees
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Re: Citroen c5 X7 Xenon headlight retrofit on steel sunspension

Unread post by Kees »

Yes, you're right, sorry, my mistake .
Dzony97
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Re: Citroen c5 X7 Xenon headlight retrofit on steel sunspension

Unread post by Dzony97 »

Is the Headlight Adjustment ECU different by part number for hydro and steel suspension?
But it makes no sense because it can be recoded with diagbox to a steel suspension, and after recoding, I'm getting faults for Vehicle height and sensor signals.
To me, it seems that the ECU is not even reading sensor signals. All thought height sensors are working (tested them on the bench)
On the other side, ECU is sending 5V on the sensor signal wire (pin 2 on the sensor and pin C2 and C3 on the ECU side), and 1, which should be 5V, I'm reading only from 1.2 to 4.5V with the sensor not even being connected. The whole thing is driving me crazy, since that is the only thing that should be done for it to work properly. Bi xenon headlights are like the best thing, way much better than the halogen ones that I had on the car before. Since they went down all the way when I plugged in the ECU, I went to a local mot and lifted them on the screw adjusters. Just for a few days till I find a way to make it work.
Kees
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Re: Citroen c5 X7 Xenon headlight retrofit on steel sunspension

Unread post by Kees »

The 5V on the sensor shoud be on pin # 1, signal #2 and ground #3.
If you look at the sensor with the arm towards you, pin #1 is on the left side.
20250704_093559.jpg
Red wire => 5 Volt
Dzony97
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Re: Citroen c5 X7 Xenon headlight retrofit on steel sunspension

Unread post by Dzony97 »

Based on the provided diagrams, the signal wire is receiving a 5V potential. To further diagnose the issue, I propose supplying the sensor with 5V from a dedicated power supply and subsequently verifying the readings via Diagbox. Multiple inspections of the diagrams and wiring have been conducted to rule out any potential misconnections, yet the signal wire continues to exhibit a 5V reading even without the sensor being plugged in.
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Gibbo2286
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Re: Citroen c5 X7 Xenon headlight retrofit on steel sunspension

Unread post by Gibbo2286 »

My thoughts on all that.............why?
Anyone who has never made a mistake has never tried anything new. (Albert Einstein)
Kees
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Re: Citroen c5 X7 Xenon headlight retrofit on steel sunspension

Unread post by Kees »

Did you check the voltage between B2 and C1 if there are the 5 Volt, and also witch is the minus.
If C2 and C3 also measure 5 Volt, it's possible, that there's a pull-up resitor inside.
Sometimes the wire diagram is different.
Dzony97
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Re: Citroen c5 X7 Xenon headlight retrofit on steel sunspension

Unread post by Dzony97 »

Gibbo2286 wrote: 04 Jul 2025, 10:34 My thoughts on all that.............why?
Well, bi xenon lights are way better than halogen ones. :) and i like to retrofit stuff. :)
Dzony97
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Joined: 12 Aug 2021, 22:17
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Re: Citroen c5 X7 Xenon headlight retrofit on steel sunspension

Unread post by Dzony97 »

Kees wrote: 04 Jul 2025, 10:47 Did you check the voltage between B2 and C1 if there are the 5 Volt, and also witch is the minus.
If C2 and C3 also measure 5 Volt, it's possible, that there's a pull-up resitor inside.
Sometimes the wire diagram is different.
I will check tonight when i come home from work. :)