[kgeddes]

I have a 2002 L322 V8 Vogue with xenon headlights which has developed a problem. It quite difficult to explain but here goes!

When I switch the dipped beam on all is ok, however after a few minutes the full beam light on the dash illuminates. If I push the lever forward the blue light remains on and if I switch to side lights only the blue light remains illuminated!

If I look at the headlamps: when they are working correctly in dipped beam the upper lamp only illuminates. When the problem develops the lower lamp remains illuminated. Even when I switch to side lights only the lower lamp remains illuminated and the only way I can extinguish the lower lamp is to push the light stalk to the forward position.

I hope this in some way makes sense and would appreciate any suggestions as to what's going wrong.

Many thanks in advance.

 

[Datatek]

LCU wet going by other posts.

 

[Saint.V8]

LCU wet going by other posts.

That or K bus issues....iirc the dash lamps are controled via the K bus...research will confirm or refute.

 

[kgeddes]

Thanks guys, where is the LCU located please? Cheers

 

[Saint.V8]

Thanks guys, where is the LCU located please? Cheers

Drivers (UK) A pillar half tucked up the side of the dash...

Remove the tread plate on the sill, remove the plastic A pillar trim, look upwards for a long(ish) black rectangle with grills on it...that's the LCM

 

[kgeddes]

Drivers (UK) A pillar half tucked up the side of the dash...

Remove the tread plate on the sill, remove the plastic A pillar trim, look upwards for a long(ish) black rectangle with grills on it...that's the LCM

Thank you, found it ok. How do I remove it? I can see one bolt at the bottom of the unit but is there one at the top?

 

[Saint.V8]

Thank you, found it ok. How do I remove it? I can see one bolt at the bottom of the unit but is there one at the top?

Nope just the one bolt....the top slides into a locator peg, so undo the bolt, slide it down a tad, take the connectors off and then withdraw....

 

[kgeddes]

Nope just the one bolt....the top slides into a locator peg, so undo the bolt, slide it down a tad, take the connectors off and then withdraw....

Thanks again, removed and looks ok, no signs of dampness.

I know this has been covered in other threads but I would just like to be clear. If I fit a 'known to be working as it should' used LCM what will the effect be?

I have read about the 'tampered with' dot and the mileage recording but could it affect other functions on the vehicle?

As always, any help greatly appreciated.

 

[Saint.V8]

Aslong as it is 'like for like' i.e. Xenon Headlamps against Halogen Lamps it should be OK...

I found that when I substituted mine for another, I got the tamper dot and also a false brake lamp failure warning...didn't solve my issue so I replaced my original LCM and the tamper dot went and the lamp failure warning also went!!

Mileage should remain as the 'Master' recording is in the instrument pack ECU....

 

[kgeddes]

Aslong as it is 'like for like' i.e. Xenon Headlamps against Halogen Lamps it should be OK...

I found that when I substituted mine for another, I got the tamper dot and also a false brake lamp failure warning...didn't solve my issue so I replaced my original LCM and the tamper dot went and the lamp failure warning also went!!

Mileage should remain as the 'Master' recording is in the instrument pack ECU....

Thanks again! When you say 'like for like' are there two types of LCM? One for xenon and one for halogen?

 

[Saint.V8]

Thanks again! When you say 'like for like' are there two types of LCM? One for xenon and one for halogen?

As far as I know there is...as the LCM would need to know the bulb failure criteria and also how to tell the headlamps to fire up....be it telling the ballast to strike or a MOSFET thingy(?) in the LCM to power the halogen lamp!

 

[2.0_hippo]

You can select which type of headlight (xenon or halogen) within the LCM programming pages

Can also modify the bulb checking criteria

 

[kgeddes]

As far as I know there is...as the LCM would need to know the bulb failure criteria and also how to tell the headlamps to fire up....be it telling the ballast to strike or a MOSFET thingy(?) in the LCM to power the halogen lamp!

More confusion! The LCM I am looking at in my vehicle appears to be YWC000540 but I am now advised I need part number YWC000500 (by Rimmer Bros). YWC000500 does not look anything like YWC000540.....can anybody clarify please?

Hope this makes sense Thanks again?

 

[Saint.V8]

As far as I know, the YWC000540 was replaced a few times and the current part number is YWC500282

 

[kgeddes]

As far as I know, the YWC000540 was replaced a few times and the current part number is YWC500282

Rimmer Bros have confirmed. As you say, the current part number is YWC500282 (not sure where he got YWC000500 from!).

So, i need used part number YWC000540 which was previously installed in a Vogue with xenon headlights. I'll let you know how it goes. Many thanks, once again.

 

[kgeddes]

Had the vehicle our last night and the lights were back to normal, working as they should......but......this morning back malfunctioning!

 

[holidaychicken]

have you had the vehicle connected up to any diagnostics ?

 

[kgeddes]

have you had the vehicle connected up to any diagnostics ?

No, not yet. Out in it again tonight and the fault is now intermittent. With dipped lights engaged the main beam lights are flickering on and off. Previously the main beam lights were engaging with the dipped lights all the time but not to full brightness.

 

[holidaychicken]

Sounds like a poor connection somewhere, have you done anything out of the ordinary recently, repaired anything, replaced anything or was it just totally out of the blue?
Diagnostics are a big help but i have found that these vehicles don't follow ordinary wiring rules due to the canbus system. The most simple of faults can cause all sorts of issues and sometimes the fault is with what you would think is a completely unrelated system.
Have you checked the headlight leveling ECU if you have one in the passenger foot well, its in a similar place to the LCM but on the passenger side but mounted almost on the floor in an area prone to leaks?
The headlamp levelling ECU is only fitted to models between the following VINs; 2A100042 and 3A117361.

Did you check to see if you have an aftermarket LED bulbs anywhere, front sidelights etc ?

 

[kgeddes]

Sounds like a poor connection somewhere, have you done anything out of the ordinary recently, repaired anything, replaced anything or was it just totally out of the blue?
Diagnostics are a big help but i have found that these vehicles don't follow ordinary wiring rules due to the canbus system. The most simple of faults can cause all sorts of issues and sometimes the fault is with what you would think is a completely unrelated system.
Have you checked the headlight leveling ECU if you have one in the passenger foot well, its in a similar place to the LCM but on the passenger side but mounted almost on the floor in an area prone to leaks?
The headlamp levelling ECU is only fitted to models between the following VINs; 2A100042 and 3A117361.

Did you check to see if you have an aftermarket LED bulbs anywhere, front sidelights etc ?

Thank you very much for your suggestions. The lighting problem has been there for some time on a very intermittent basis but became significantly worse following replacement of the alternator. I will check the items you suggest and report back.