Xc90 ABL - One has Error Code

[benjyman86]

Hi there,

So I'm not sure if this can be programmed as a reset, if this is HCM, the light itself etc.? My 2016 XC90 came with active bending lights. Only the right side bends though. I have an error code of B128A01 - Left Head Lamp. General Electrical Failure. I'm pretty sure this is the 'why' as this is the one which doesn't bend.

No warning lights however on dash.

Now, could this be reset somehow? I don't know where to start with what would even need replacing here? The light unit maybe? It does go up and down when i start the car. Or would it be HCM?

If I get a new light and that's what is needed, would I need to programme it? Assuming not if using same HCM.

Help much appreciated

Sent from my Pixel 8 Pro using Tapatalk

[BOSS89]

I‘ve got the Same Problem. Did you solve it?

[benjyman86]

Not yet. But, having found on some Swedish forum it is usually electrical connections on one of the modules. I haven't had a chance to get the lamp out yet as weather has been awful, but might do this weekend. My plan is remove it (after removing the bumper), remove all modules and then spray electrical contact cleaner on everything to clean it down.

This Swedish guy said it is a fault due to a temperature sensor tripping in and out on the light so it disables some features because it can't tell if it is overheating (so he said). But it fixed it for him.

Found his post here as part of a wider conversation. http://volvosweden.se/forum/viewthread.p...ad_id=1278

Sent from my Pixel 8 Pro using Tapatalk

[BOSS89]

Not yet. But, having found on some Swedish forum it is usually electrical connections on one of the modules. I haven't had a chance to get the lamp out yet as weather has been awful, but might do this weekend. My plan is remove it (after removing the bumper), remove all modules and then spray electrical contact cleaner on everything to clean it down.

This Swedish guy said it is a fault due to a temperature sensor tripping in and out on the light so it disables some features because it can't tell if it is overheating (so he said). But it fixed it for him.

Found his post here as part of a wider conversation. http://volvosweden.se/forum/viewthread.p...ad_id=1278

Sent from my Pixel 8 Pro using Tapatalk

I will do the Same. Also Waiting for better Weather

[benjyman86]

So I have taken my light out, removed all the modules, cleaned with contact cleaner and nothing. I can get replacement modules (it has 4, but the smaller one has no codes on it but is the one with fins and much smaller). The whole lamp even used is super expensive, but I don't know which module does active bending lights? Any clues from anyone here? If not, might ask the volvo dealership - they probably won't be interested as I'm sure they'd love to sell me a new unit . I have taken the photos of the modules here though.

Sent from my Pixel 8 Pro using Tapatalk

[TheKris79]

Hello,

Very new to this forum, but found this thread and wanted to mention that in my XC90 First Edition D5 I have had the same fault. As I live in Sweden I have been fiddling around this for years now. The first light gave fault and did not operate at around 125 000 km and I managed to get a used one from local dismantling place (driven 5000km) which now have started to act up again. Now the car has 230tkm. So it seems that they last about 100tkm.
Since I kept the old light with me I teared it apart completely to see how the interiors look like and much to my testing I could not find any issues, but I can post here loads of pictures from these internal parts and maybe someone with good electronic skills can give some hints.
There is a 4 different led modules each of which has quite serius cooling fins, but only under 1 (daylight element) there is actual cooling fan. Now here in volvoservice the guys told me that some people have added extra fan and that has worked so I am exploring this at the moment.
Another item I noticed that there is the ventilation mesh at the backside of the light which does not really seem to let air through so I am planning to change that to a different material to see if it makes any difference.
Also what I noticed there are internal screws that allows you to swivel approx 4mm the daylight module inside (though the access is quite bad) which gives a bit more space between the fan and heat sink.
As I will start dealing with this now thwn probably I will add some information here in the future if you like.
Let me know if pictures are welcome from the interior of the light and I will try to figure out how to post them.
Also worth mentioning that this issue will not be fixed by changing any of the external modules since it is some internal heat calculation or chip that gives the error. 
I could not find such resistor but maybe you guys would be able to tell how it should look like.
I will be able to take some pics next week so hopefully it might help.
The bending part of the light has a separate motorized unit inside the lamp that turns the upper light left and right so it is controlled by one of the aluminium modules and based on the internal wiring it is connected to both of them. The black module is the up-down controller.

[benjyman86]

Hello,

Very new to this forum, but found this thread and wanted to mention that in my XC90 First Edition D5 I have had the same fault. As I live in Sweden I have been fiddling around this for years now. The first light gave fault and did not operate at around 125 000 km and I managed to get a used one from local dismantling place (driven 5000km) which now have started to act up again. Now the car has 230tkm. So it seems that they last about 100tkm.
Since I kept the old light with me I teared it apart completely to see how the interiors look like and much to my testing I could not find any issues, but I can post here loads of pictures from these internal parts and maybe someone with good electronic skills can give some hints.
There is a 4 different led modules each of which has quite serius cooling fins, but only under 1 (daylight element) there is actual cooling fan. Now here in volvoservice the guys told me that some people have added extra fan and that has worked so I am exploring this at the moment.
Another item I noticed that there is the ventilation mesh at the backside of the light which does not really seem to let air through so I am planning to change that to a different material to see if it makes any difference.
Also what I noticed there are internal screws that allows you to swivel approx 4mm the daylight module inside (though the access is quite bad) which gives a bit more space between the fan and heat sink.
As I will start dealing with this now thwn probably I will add some information here in the future if you like.
Let me know if pictures are welcome from the interior of the light and I will try to figure out how to post them.
Also worth mentioning that this issue will not be fixed by changing any of the external modules since it is some internal heat calculation or chip that gives the error. 
I could not find such resistor but maybe you guys would be able to tell how it should look like.
I will be able to take some pics next week so hopefully it might help.

This is great and I found by trial and error that the modules like you say don't actually alter the reference that it gives back to the CEM. I had been at a bit of a stuck point until I can get a used unit like you did. It would be good to understand if there's a 'fix' that can be adapted for the temperature, but I would imagine it is a resistor (thermistor?) that has burnt out isn't it? I say that as it will immediately trigger on my one. It intermittently will work, sometimes I can go multiple drives and it works, then I get nothing for a week or 2, then it's back and then I can go for a drive to the shops and it doesn't work, but driving home it does. Very odd where it will intermittently pass it's own tests. I have found some electrical experts locally but none of them would touch it as they don't think that they could save it due to lack of knowledge of the wiring and schematics so the effort vs benefit wasn't worth it for them frustratingly. I haven't got a spare for me to strip it down either anyway. I did do electronics at college but that was many, many years ago!

So I'd be interested to see what the internals look like, the error code is supposedly due to temperature like you say, but I am not entirely sure which circuit that would be or if cooling after it has already got to this point will help, but would be interested to see?!

Thanks

Ben

Sent from my Pixel 8 Pro using Tapatalk

[ElectricEel]

So I have taken my light out, removed all the modules, cleaned with contact cleaner and nothing. I can get replacement modules (it has 4, but the smaller one has no codes on it but is the one with fins and much smaller). The whole lamp even used is super expensive, but I don't know which module does active bending lights? Any clues from anyone here? If not, might ask the volvo dealership - they probably won't be interested as I'm sure they'd love to sell me a new unit . I have taken the photos of the modules here though.

Sent from my Pixel 8 Pro using Tapatalk

Black module is responsible of ABL swiveling bending function. Like in P3 platform.

[TheKris79]

So I have taken my light out, removed all the modules, cleaned with contact cleaner and nothing. I can get replacement modules (it has 4, but the smaller one has no codes on it but is the one with fins and much smaller). The whole lamp even used is super expensive, but I don't know which module does active bending lights? Any clues from anyone here? If not, might ask the volvo dealership - they probably won't be interested as I'm sure they'd love to sell me a new unit . I have taken the photos of the modules here though.

Sent from my Pixel 8 Pro using Tapatalk

Black module is responsible of ABL swiveling bending function. Like in P3 platform.

Hmmm... based on the connection point mechanically it is only responsible for moving the lights up and down as it has a physical and electrical connection only to that screw which moves the up-down part. Unfortunately I am travelling this week and be back at home on Saturday so then I can post pictures of the mechanical parts and how they are connected during weekend. I believe that the black module gets the input from the height sensors and adjusts accordingly, but the bending function is receiving the signal via the other 2 modules(that is based on the electrical wiring inside the light so I might be wrong of course over here).
Mine is also having the issue occasionally and sometimes out of nowhere when turning left it suddenly starts operating while driving.
Apparently it is so that the system cuts off both lights eventually when 1 of them sends an error message, but it seems to be a problem always related to the left light for some reason.
I did question the ecm ventilation that is having a pipe opening directed exactly under the left light, but apparently that is the suction side of the function so it should not make difference at least that was told by volvo mechanics.
As mine started to act up again about 3 weeks ago then this time I do want to get to some result instead of paying the volvo fees of 2000 usd for it to buy new one( no point of getting used version if it acts up the same way). You cant purchase new exact version as they dont sell it anymore and have to buy 2 new lights with different modulrs which can go up to 4500 usd unfortunately. To me that seems that volvo has realized there is a problem with these but are not willing to recognize it and as they know there is not so many first year cars out there they dont bother. The new versions are from 2018 onwards.

[TheKris79]

Finally had a chance to make some pictures.
I try to attach many items so hopefully they will go through.
First should be showing the whole internal of the light. Second is the turning led module with mechanical black element underneath. Then is the led module right below which seems to be cooled with ventilator. Did not take a close pic from the high beam modules.
Then there is a separate open card on the left bottom pointed with my thumb.
Took the pics also from the boards with led diodes so in case someone could point to the temp resistor would be good. Hopefully the pictures are in order.
If you need more pics just let me know