Headlight Wiring Xenon/LED and Halogen

[rost2527]

I have purchased a lovely 2011 CT200h yes it has got some, ok maybe a lot of history (not in a good way) but i love the car and in a great drive especially in London UK.  It was previously a CAT D/Accident Damage and has had front end damage.  The problem is that the car should have Xenon/LED headlight and the cowboys who repaired it have put Halogen headlights guessing due to the cost (all this was done before i purchased the car).  I have gone through all the wiring and now all the lights including DRL's work correctly as per the Lexus Workshop Manual.

This is now were the problem lies, i have always had a CHECK HEADLIGHT SYSTEM warning on the dashboard when the low beam comes on looking at the wiring diagram the halogen low beam has just two wires + and - where as Xenon/LED low beam has three wires + and - plus a BLACK wire from the MAIN BODY ECU (which is currently not connected to anything) which i am guessing is to do with the canbus system?!  If this is the case does anyone know what signal the BLACK wire is expecting to send back to the MAIN BODY ECU.  If i put a voltage meter on it i have 12v coming down the BLACK wire, i have tried linking it in with the + wire for the low beam to see if that work but to no avail.

HELP please i just want to get the message off the dash.

Thanks in advance.

Roy

[ColinBarber]

What has been done to the auto levelling feature? HID lights will have this feature, halogen lights will not.

[rost2527]

That’s another thing I need to look at, the wiring on the Lexus Workshop Manual is the same, at the moment I have adjusted the headlights manually till I can sort it out.  I’ll save this one for another rainy day! 🤔

[stormchaser]

Would it be the Black wire to the Can system is searching for a complete circuit and any voltage drops hence throwing up an error code?


Sent from my Iphone using Tapatalk

[rost2527]

I did try and link the black wire with the positive wire to see if a voltage drop when the low beam came on, and it didn't work.

[ColinBarber]

I don't believe the black wire is CAN connected. It is directly into the body ECU. Not sure what it is for, will need to do some research. It is the self levelling that often triggers a check headlight system warning.

[rost2527]

Thats what i thought but there is a different fault message for the headlight level system in the owners manual.

[Petar]

On 4/14/2018 at 8:31 PM, rost2527 said:

I have purchased a lovely 2011 CT200h yes it has got some, ok maybe a lot of history (not in a good way) but i love the car and in a great drive especially in London UK.  It was previously a CAT D/Accident Damage and has had front end damage.  The problem is that the car should have Xenon/LED headlight and the cowboys who repaired it have put Halogen headlights guessing due to the cost (all this was done before i purchased the car).  I have gone through all the wiring and now all the lights including DRL's work correctly as per the Lexus Workshop Manual.

This is now were the problem lies, i have always had a CHECK HEADLIGHT SYSTEM warning on the dashboard when the low beam comes on looking at the wiring diagram the halogen low beam has just two wires + and - where as Xenon/LED low beam has three wires + and - plus a BLACK wire from the MAIN BODY ECU (which is currently not connected to anything) which i am guessing is to do with the canbus system?!  If this is the case does anyone know what signal the BLACK wire is expecting to send back to the MAIN BODY ECU.  If i put a voltage meter on it i have 12v coming down the BLACK wire, i have tried linking it in with the + wire for the low beam to see if that work but to no avail.

HELP please i just want to get the message off the dash.

Thanks in advance.

Roy

 I have probably the same problem with my car which is ct200 premier ,plate 61., bought a year and a half ago. I’ve been told from the seller that the car had light incident on the front bumper and fully repaired, no category recorded. Anyway I have the warning light CHECK THE HEADLIGHT SYSTEM on every time when the low beam comes on !! Very annoying, I’ve been on diagnostics and the fault code which coming out is B2430- LED headlight LH and the mechanic can’t find the problem cause everything works fine !! So I’m wondering did you manage to fix it, cause the fellas at lexus service want from me £400 just  tell me is the headlight ecu faulty or not, but not to repair  it!!