C5 Aircross: Full-LED Headlights - Dipped Beam Fault "B1137 12"

This is the Forum for all your Citroen Technical Questions, Problems or Advice.

Moderator: RichardW

User avatar
JimmyTulip
Posts: 6
Joined: 03 Apr 2024, 08:52
x 1

C5 Aircross: Full-LED Headlights - Dipped Beam Fault "B1137 12"

Post by JimmyTulip »

Hello,

I have a C5 Aircross from 2019 with Shine-Pack and Full-LED headlights.

VIN: VR7**************[VIN obfuscated, can be read by forum staff]

In general ALL lights are working. When driving with High-Beam, visibility is great.
But I am annoyed by the poor visibility when driving with Dipped-Beam. On Dipped-Beam the lights point to low to ground and it is dangerous to drive, because you might see an obstacle too late.

At first I thought the headlights might be out of alignment and I was thinking to adjust them by the alignment screws.
But before I did anything I did connect the car up with DiagBox to read the fault-codes and unfortunately there was a fault related to the headlights:
Diagbox_B1137-Fault.png
B1137 12 - Fehler Ansteuerung des Abblendlichts vorne rechts (Kurzschluss an Plus)

I'm sorry, but the error on the sceenshot above is shown in german. The error should translate to something like:

B1137 12 - Right dipped beam control fault (Short circuit to positive)

I can clear the fault, but it comes back immediately, I think, after ignition off - ignition on or when switching on the headlights.


The handbook says, that in the event of a fault, the system places the headlamp beams in the lowest position:
Auto-Adjust headlamps - Handbook.png
And I think this is what is happening here and this may cause the poor visibility. Despite I DON'T get a warning on the instrument panel.
I can NOT remember, if the lights did a self-test on startup? I think they went up and down after ignition on, but I am not sure anymore.
However, at the moment they don't do something like that on startup.


I did have a close look on the headlight-connector, but I did NOT find anything suspicious:
LED-Headlights_Male-Connector_HL-Side.jpg
LED-Headlights_Female-Connector_Cabling-Side.jpg
I followed the cabling back behind the engine without taking anything apart and I was not able to find any visual damage or anything suspicious ...

I also took a photo of the part number of the headlight itself:
LED-Headlights_Part-Number.jpg
Normally I am a DIY-guy, but I do NOT have access to any information from Citroen. (service manual, wiring diagrams, ...)
I was not able to find anything helpful on the Internet.

Any tips? How should I proceed?

Thank you
User avatar
GiveMeABreak
Forum Admin Team
Posts: 37780
Joined: 15 Sep 2015, 19:38
x 5820

Re: C5 Aircross: Full-LED Headlights - Dipped Beam Fault "B1137 12"

Post by GiveMeABreak »

There's probably not a lot you can do with this - apart from getting the dealer to check it out as the LED units are pretty much self-contained. There is a driver unit and the headlamp, so either could be faulty, or an issue with the BSI. The fault descriptor is below. If it's the headlamp internally, then it's a new lamp I'm afraid. But I would check the connector and the pins very carefully to ensure they are making contact and that there is no corrosion. Give the connector a spray with some electrical contact cleaner spray and try to see if this makes any difference.

Fault Code: B1137 12
Description of Fault: Front right dipped headlamp control fault: Short circuit to positive. Lamps not controlled.
Short-circuit to positive detected for 2s.

Conditions of activation of the diagnostics
The following conditions have to be met:
- Vehicle stationary
- Ignition on
- Not in economy mode
- Triggered
Conditions for Fault to clear:
  • Absence of malfunctioning and activation of the control (For 2 seconds)
Downgrade Modes whilst Fault is active: -
Symptoms:
  • Malfunctioning of the dipped beams
  • Malfunction of the cornering or junction lighting
  • Malfunction of the front foglamps
  • Automatic lighting failure
Suspect Areas:
  • Built-in systems interface
  • Headlamp
Please Don't PM Me For Technical Help

Marc
User avatar
JimmyTulip
Posts: 6
Joined: 03 Apr 2024, 08:52
x 1

Re: C5 Aircross: Full-LED Headlights - Dipped Beam Fault "B1137 12"

Post by JimmyTulip »

Hello @GiveMeABreak,

Thank you very much for the fault descriptor!

Yes, I have cleaned the connector using contact cleaner, but it did not make any difference.

When I read about "Short circuit to positive" I was all-in on the wiring-side.
The fault descriptor also does not contain anything about the wiring?
May I rather exclude a fault from the wiring-side?

Do you perhaps know for sure, if the lights normally do a self-test on startup? (move up and down)

Thank you
User avatar
GiveMeABreak
Forum Admin Team
Posts: 37780
Joined: 15 Sep 2015, 19:38
x 5820

Re: C5 Aircross: Full-LED Headlights - Dipped Beam Fault "B1137 12"

Post by GiveMeABreak »

No, not on these, that used to be a feature of the Xenon directional lighting, not the LEDs which are static I believe. I think only some later top models have active matrix LED lighting.
Please Don't PM Me For Technical Help

Marc
User avatar
JimmyTulip
Posts: 6
Joined: 03 Apr 2024, 08:52
x 1

Re: C5 Aircross: Full-LED Headlights - Dipped Beam Fault "B1137 12"

Post by JimmyTulip »

Image

Assuming I would get a new headlight with the same part number as mine "9816925280" (new or second hand):

I know the headlight(s) would have to get adjusted using a car headlight tester, but ...
Would the new headlight has to be coded somehow into the system or will it work out of the box? (Plug and Play)

Thank you
User avatar
GiveMeABreak
Forum Admin Team
Posts: 37780
Joined: 15 Sep 2015, 19:38
x 5820

Re: C5 Aircross: Full-LED Headlights - Dipped Beam Fault "B1137 12"

Post by GiveMeABreak »

Not as far as I'm aware.
Please Don't PM Me For Technical Help

Marc