GOLF 7 GTI LIGHT ASSIST FAULT

[Nizam90432]

Hi guy's
I have picked up a problem with my High Beam light assist. As soon as i try to activate its gives me a fault "Light Assist"
Any ideas as to what has gone wrong.
I

 

[DV52]

what happens to the high-beam? Is that the exact message? Have yoiu done anything to the car in the interim (made changes to module coding)?

 

[Nizam90432]

what happens to the high-beam? Is that the exact message? Have yoiu done anything to the car in the interim (made changes to module coding)?

Hi Buddy,
I havent done anything on the car, The had gone in last month for the 60k service, and 2 weeks I had a blown conering bulb which i changed.
Last week driving at night decided to use the light assist and the fault popped out

 

[Julian1]

Hi buddy, I have the same problem for 4 years now and I have mentioned it to VW on every maintenance schedule and they can't fix it either. Cannot reset it either using the diagnostic tool. Help!

 

[Hlynx111]

I have the same problem with my car. I wasn't sure if I had high beam assist until I saw that there was a camera for it in the rear view mirror. Everytime I try to switch on my high beams I get this fault. It even tells me that there is a fault from the car menu on the middle screen. From some research it seems like GTI's made before 2017 have the necessary hardware to use high beam assist (ie camera) but not the software. There are people who have changed the coding their cars to allow them to use high beam assist but I haven't found anyone talk about the faults before.

 

[The Fed]

Only ROW having this problem?

 

[Hlynx111]

Only ROW having this problem?

Sorry what does ROW mean?

 

[DV52]

RoW=Rest-of-world
It's the manufacture's view of the importance of "Germany"!!. Just joking - it's really a catch-all descriptor for the "other" countries" that aren't included in set-models like NAR (North American Region).

As for the original problem - I'm guessing, but the lighting fault very much sounds like someone has re-coded the BCM (the module @ address hex09). If Nizam can find a forum colleague that has access to a diagnostic cable -perhaps check Byte 2, Bits 0-2 in the module's long-code which are the software switches for Advanced High-beam control

Here are the setting options for these Bits:
Halogen=hex0
Halogen_main_beam_assist=hex1
Xenon_AFS=hex2
Xenon_AFS_and_main_beam_assist=hex3
Bi-xenon_AFS=hex4
Bi-xenon_AFS_and_main_beam_assist=hex5
Bi-xenon_AFS_and_MDF_GLW= hex6

AFS, (Advanced Frontlighting System) = dynamic cornering light (Initialisation for the cornering light CAN bus)
Main beam assist = Assistance system which supports the driver when changing from main beam to low beam headlights, in order to prevent dazzling other road users.

Make sure that the setting for this Byte/Bits matches the equipment that's physically installed on the car - perhaps?

Don

PS: apology for the techno-babble!!

 

[Hlynx111]

RoW=Rest-of-world
It's the manufacture's view of the importance of "Germany"!!. Just joking - it's really a catch-all descriptor for the "other" countries" that aren't included in set-models like NAR (North American Region).

As for the original problem - I'm guessing, but the lighting fault very much sounds like someone has re-coded the BCM (the module @ address hex09). If Nizam can find a forum colleague that has access to a diagnostic cable -perhaps check Byte 2, Bits 0-2 in the module's long-code which are the software switches for Advanced High-beam control

Here are the setting options for these Bits:
Halogen=hex0
Halogen_main_beam_assist=hex1
Xenon_AFS=hex2
Xenon_AFS_and_main_beam_assist=hex3
Bi-xenon_AFS=hex4
Bi-xenon_AFS_and_main_beam_assist=hex5
Bi-xenon_AFS_and_MDF_GLW= hex6

AFS, (Advanced Frontlighting System) = dynamic cornering light (Initialisation for the cornering light CAN bus)
Main beam assist = Assistance system which supports the driver when changing from main beam to low beam headlights, in order to prevent dazzling other road users.

Make sure that the setting for this Byte/Bits matches the equipment that's physically installed on the car - perhaps?

Don

PS: apology for the techno-babble!!

So i work at an Audi dealership, and i asked one of the techs to scan it (should have done that in the first place) and it came up with the fault. It then said to replace the "high beam assist" module or something along those lines... It gave us the part number J844 but i cant find it or a even a mention of it anywhere.

 

[DV52]

So i work at an Audi dealership, and i asked one of the techs to scan it (should have done that in the first place) and it came up with the fault. It then said to replace the "high beam assist" module or something along those lines... It gave us the part number J844 but i cant find it or a even a mention of it anywhere.

OK - I'm not a big fan of ODIS (the dealer tool) - it's OK for "standard" stuff, but it tends to fall-over when faults are caused by sloppy code changes caused by errant users of diagnostic cables.

Anyway, there nothing secret about J844 - I'm very surprised that an Audi dealer hasn't heard of the module because it's also in the Audi A3 8V (which like the mk7, is also built on a MQB platform).

J844 is indeed the main-beam assist control module and it normally lives @ address hex20 on the CAN network. I've not actually worked on one of these modules, but I suspect that it might reside as part of the anti-dazzle rear vision mirror housing.

Of course, the actual part number will depend on your particular version mk7, but just as a sample: for a 2015 1.6 TDI (RoW), J844 = 5G0 857 511 D. I don't have access to these part numbers, but I suggest that you remove the module on your car and read it's label. Here's a diagram showing the typical location of J844:

Don

 

[Hlynx111]

OK - I'm not a big fan of ODIS (the dealer tool) - it's OK for "standard" stuff, but it tends to fall-over when faults are caused by sloppy code changes caused by errant users of diagnostic cables.

Anyway, there nothing secret about J844 - I'm very surprised that an Audi dealer hasn't heard of the module because it's also in the Audi A3 8V (which like the mk7, is also built on a MQB platform).

J844 is indeed the main-beam assist control module and it normally lives @ address hex20 on the CAN network. I've not actually worked on one of these modules, but I suspect that it might reside as part of the anti-dazzle rear vision mirror housing.

Of course, the actual part number will depend on your particular version mk7, but just as a sample: for a 2015 1.6 TDI (RoW), J844 = 5G0 857 511 D. I don't have access to these part numbers, but I suggest that you remove the module on your car and read it's label. Here's a diagram showing the typical location of J844:

Don

Thanks for you help, wow you know a lot of stuff... My car is a 2015 MK7 GTI, i have no idea how to remove the module and cant find anything online that helps me out with that. I don't want to break anything, should i take it to the Volkswagen dealership?

 

[DV52]

hmm........ not really, I wish that I knew much more stuff!!!. So, first question - does your MY15 mk7 have a front facing camera? It should be on the top the windshield, just behind the rear vision mirror. I'm not referring to the rain-light sensor Second question - does your car have Xenon headlights?Third question how are you engaging HBA (1 x push on the high beam stalk)? What happens if 2 x pushes on high bean stalk? Fourth question I know you get the message, but do the high beams actually work?

Don

 

[Hlynx111]

Yes it does have the camera. It has the base halogen headlights and the high beams do work. When i try to push the stalk for the first time after starting the car i get the fault but the high beams do turn on, after that i dont get the fault when i push the stalk for the high beams. At any point if i push it twice it gives me the fault.

 

[DV52]

hmmm........ it would be good to see a scan from a diagnostic device. Do you know anyone who has one?

 

[Hlynx111]

I do not other than at the Audi dealership i work at. When they scanned it, it said there was a fault in the High beam assist control module.