2015 Q7 TDI Prestige - passenger high beam headlight doesn't come on

[jwt27ta6]

Hello Audi lovers and experts!
I'm new to this car. I can't find anything on the web or ross-tech that fits this issue. Any ideas?
It has adaptive lights and I think Xenon lights (they are the round type).
I believe that the low and high is the same bulb, but just some physical cover opens up for high beams.
On the driver side, I can hear something mechanical happening and visibly it looks like a cover opens up


Here is the fault. All other lights work as should.

Wednesday,22,November,2023,13:12:01:04801
VCDS Version: Release 23.11.0 (x64) Running on Windows 11 x64
www.Ross-Tech.com

Address 55: Headlight Range Labels: 4F0-910-357.lbl
Control Module Part Number: 4L0 910 357 B HW: 4L0 907 357 B
Component and/or Version: AFS 1 H01 0010
Software Coding: 0000032
Work Shop Code: WSC 31414 790 00001
Additional Info: 7L6941329A AFS-Modul links H07 0004 7L6941329A AFS-Modul rechtsH07 0004
VCID: 2B031645EF041C42AA1-807E
1 Fault Found:

03798 - Output Module 2 for Right Headlamp
004 - No Signal/Communication - MIL ON
Freeze Frame:
Fault Status: 11100100
Fault Priority: 2
Fault Frequency: 1
Reset counter: 62

 

[Uwe]

No Signal/Communication

Wiring problem, or that Output Module is bad.

-Uwe-

 

[jwt27ta6]

Ok. Thank you. So where is that output module? Inside the headlight?

 

[Bruce]

Get official factor information - see the How to Drop down in the blue bar at the top of the page. Component locations are given in that repair information.

 

[jwt27ta6]

Thanks Bruce.
So what link do you mean?
https://erwin.audiusa.com/erwin/showHome.do - don't have login
http://www.bentleypublishers.com/Audi/technical-training - this didn't have info for 2015 Q7 TDI, only 2007-2009

partslink24

http://www.bentleypublishers.com/bosch/ - this didn't seem specific to any car

 

[Bruce]

https://erwin.audiusa.com/erwin/showHome.do - don't have login

Yes, you have to buy the service. It's like $35 to do so.

 

[jwt27ta6]

ok, perfect. Will do! Thank you, Bruce!

 

[jwt27ta6]

This is not very economical, esp since it will probably take more than 1 day to ultimately troubleshoot.
Choose the subcription term you want:

• One day -- $35.00
• Three days -- $60.00
• One month -- $250.00
• One year -- $2,000.00

Does anyone know where to find this module: 03798 - Output Module 2 for Right Headlamp?

 

[siLc]

You buy the one day option and download everything about your vehicle (and anything else). Then it has served it's purpuse.

Those modules are attached to the headlight housing usually.

 

[jwt27ta6]

Thank you siLc!
Yeh, I get it, but I'll probably fail to get the very doc I need. lol

Another way I guess is this:

2015 Audi Q7 TDI Prestige Sport Utility Headlight Control Module. W/DIRECTIONAL BEAM - 4L0941329 | Audi Rockville, Rockville MD

Headlight Control Module. W/DIRECTIONAL BEAM. 2015 Audi Q7 TDI Prestige Sport Utility. Genuine Audi Part - 4L0941329 (4L0-941-329). Ships from Audi Rockville, Rockville MD

parts.audirockville.com

I just have to take out the headlight to make sure this is the right part #, but I do see where it is in the diagram.

And per this video, I see supposedly how to take out the headlight (seems easy) and you can see the output module on the headlight assembly.
How to Install and Replace 2010-2015 Audi Q7 Headlight HID Xenon Bulb Instruction Tutorial - YouTube

 

[jwt27ta6]

Update to the above headlight video. U don't have to push hard at all on the outside tab. It really breaks easily. But, at least on my 2015, there is an inside locking pin thing (top back inside corner toward engine bay) that u have to completely pull up and out. See pic. (can't attach a pic...doesn't paste or like samsung or google links)

And there are 2 modules. Have to swap modules with my other q7 to see which is bad. See pic. (can't attach a pic...doesn't paste or like samsung or google links)

1. 4LO 941 329 - control module (either this is bad or some other module...probably this one)
2. 8K0.941.597.B - HID Ballast (this is working)

 

[SaVAGeSoot]

See pic. (can't attach a pic...doesn't paste or like samsung or google links)

Sticky - How To Post Pictures

The best way to post pictures is to upload them to some photo-hosting site. If you don't use a photo-hosting site, try imgur.com, you don't need to create an account there, you can just drag & drop pictures to it, and they have apps to upload pictures straight from your phone as well. Once...

forums.ross-tech.com

 

[jwt27ta6]

Update to the above headlight video. U don't have to push hard at all on the outside tab. It really breaks easily. But, at least on my 2015, there is an inside locking pin thing (top back inside corner toward engine bay) that u have to completely pull up and out. See pic. (can't attach a pic...doesn't paste or like samsung or google links...had to use imgur.com)

And there are 2 modules. Have to swap modules with my other q7 to see which is bad. See pic. (can't attach a pic...doesn't paste or like samsung or google links)

1. 4LO 941 329 - control module (either this is bad or some other module...probably this one)
2. 8K0.941.597.B - HID Ballast (this is working)

See 2 pics below.
Update: Confirmed "03798 - Output Module 2 for Right Headlamp" is module 4LO 941 329 by replacing with a known good one. So ordered one off ebay.

Next was bad alternator. I've lost some respect for audi engineers! They really couldn't put this toward top of engine???? Took all afternoon!!!

• Per tips online, removed passenger tire, fender liver, myriads of wires, sensors, air box, but could not get it out over that beam!
• However, probably was necessary, if for nothing else, just to get the 2 wires off back of alternator. What a nightmare that was. Had to unmount alternator, twist it around and then fight to get a ratchet on the nut. Ultimately, I used 3 extensions and a swivel and snaked it thru from underneath car with impact gun to finally get the nut off.
  • MAYBE could do that with alternator mounted, but still could NEVER get wire and bolt back on with alternator mounted in place. The wire is like a 2-guage (stiff) and too short.
  • And could NEVER get the 2nd wire (plug) removed while mounted.
  • MAYBE could get nut off, unmount alternator, twist it around enough to access the plug from underneath car, RATHER than from wheelwell. But wire might not be long enough to do that. Will try on re-installation.
• Took boost boots off but could not get it up in front of radiator.
• Took the lower boost tube and a piece of frame off (shield) under radiator etc etc to finally get it out! See pics.
• This is where it mounts... but it won't come out above that beam.
• 
• Moved boost tube and lower frame radiator shield out of way so it could come out the bottom
• 
  
• 
  
• 

• The next hurdle is finding a stupid new alternator 059903019f for 2015 audi Q7 TDI Prestige under $1000.....that's right, $1000.
• Found on shady websites, but don't trust.
• Found on Amazon but takes 3-4 weeks to deliver from UK
• Found at Autozone for $729 with $146 off coupon, but after 2 days, order got cancelled cause not available.
• Other boxes stores don't have the Valeo available either.
• I have an Advance Auto employee friend seeing if he can special order it with his discount.
• If nothing else, will order from
  • htthttps://parts.audirockville.com/p/Audi_2015_Q7-TDI-Prestige-Sport-Utility/Alternator-Alternator-180-Amp-Alternator/47999162/059903019F.html

 

[Uwe]

See 2 pics below.

Gibberish links.

I have an Advance Auto employee friend seeing if he can special order it with his discount.

I have little faith that Advance Auto will be able to source an alternator that works properly in your Q7. I expect it will fit mechanically, but the original is almost certainly an intelligent alternator that communicates with the BMS in the vehicle, and any sort of aftermarket part is unlikely to be able to do that.

-Uwe-

 

[jwt27ta6]

Gibberish links.


I have little faith that Advance Auto will be able to source an alternator that works properly in your Q7. I expect it will fit mechanically, but the original is almost certainly an intelligent alternator that communicates with the BMS in the vehicle, and any sort of aftermarket part is unlikely to be able to do that.

-Uwe-

Bummer. it worked for me and showed me the pics. Probably only works for me.
I corrected the post above using imgur.com.
Yeh, maybe won't.

 

[jwt27ta6]

Update on Alternator:
12/13/23 - Installed Duralast Alternator 10250 Part Number.

Reassembly:
I put the connector and the 2-gauge charging wire on while it was still unmounted, BUT could not get a wrench or socket on it. After mounting it, I was able to snake a socket with several extensions from behind the engine to finish tightening the charging wire nut. (see pic). Note: I couldn't get a good bite on nut because Alternator bolt too long for shallow socket and deep socket too long for space. So I cut a cheap deep socket to size and bingo.... got it tight!

Summary:
I think I could do this whole alternator replacement without removing what turned out to be the TPMS sensor below the alternator (didn't want to break it experimenting with different ways to attempting to get it out). But you have to remove wheel, fender liner, and airbox in order to get to the wires on back of alternator while it is unmounted (both for disassembly and reassembly). And of course the lower boot pipe, radiator sensor wire and that lower radiator shield. Next time I'll take all 4 bolts out of it and completely take off car.

Duralast alternator #10250 from AutoZone for $824.15 after 20% discount and delivered in like 4-5 days (lifetime replacements) after trying online and other box stores....nobody had Valeo 059903019F except https://parts.audirockville.com/p/47999162/059903019F.html but took 4-6 week from Germany cause none in US and https://www.ebay.com/itm/224535935033 but don't trust it and would have to ship back for warranty.

I'm on day 4 and it is charging and no codes. Just hope it doesn't fail anytime soon

 

[SaVAGeSoot]

I know this isn't much help now, but alternators can usually be rebuilt at very low cost as there isn't much to them... Considering the price, maybe look into that option if you have to do it again.

 

[jwt27ta6]

I did. And I have an old guy up the road who has made a living at it and he said he could probably do it for $150. But I've had him do other alternators and they didn't last long. So, I figured I'd have him try it and hey if he can, then I'll have a spare that might work for a few months.

 

[jwt27ta6]

Update: Replaced headlight module 2 on the headlight assembly as shown above and now passenger high beams work and no more fault on dashboard.

But now getting this fault. Was getting it before, but it came back. And now leaking antifreeze. Can't confirm where coming from but after many checks, I think the thermostat housing.
4484 - Coolant Thermostat Valve (N214)
P0128 00 [237] - Temperature below Control Range
MIL ON - Confirmed - Tested Since Memory Clear

Turns out on this particular TDI engine the decided in all their wisdom to COMBINE the oil filter housing and the thermostat housing into ONE housing and a built-in thermostat. Why have both OIL and ANTIFREEZE in SAME plastic housing??? And a non-replaceable thermostat! So crazy. From Audi $500. Found it on ebay for $50. Will update once it arrives and get it installed.

While I'm hear, I might as well ask:
I'm trying to retro fit an 8pin HBA mirror to my 6pin mirror.

1) any chance anyone could tell what the 6 pins on the 2015 Q7 TDI SLine Prestige are?
2) And what pins are the high and low of the CANBus gateway? And where is that thing?

 

[jwt27ta6]

Update: Replaced Engine Oil Filter Housing +Thermostat 059115389P and no more P0128 code nor antifreeze leaking.

BTW, I caused myself some grief when replacing the alternator and failed to tighten fully the lower bolt of the ground cable that goes from frame to motor mount on passenger side. This caused intermittent starting. Sanded all surfaces, put dielectric grease on, and fully tightened and starts every time.

And BTW the Alternator guy who has been in business for 40yrs can't find a matching stater (coils) anywhere, neither from all his contacts over the years or online.