Blinking/flashing factory LED dipped beam

[RobJH]

Hi all,

Hoping someone can help, 2017 T6 with factory LEDS, dipped beam goes off/on intermittently when on auto lights. The bulb warning light comes on but then clears once the ignition is cycled. Both left and right headlights do this but not necessarily at the same time.

VCDS produced the following codes:

Address 09: Cent. Elect.       Labels: 7E0-937-BCM-V1.clb
Control Module Part Number: 7E0 937 090 B    HW: 7E0 937 090
  Component and/or Version: BCM PQ25 Max4 H81 0744
           Software Coding: B8AE39BF4AF3341393288F206CEB9FFCC094668160CD79603204033F0860
            Work Shop Code: WSC 02737 534 631221
                      VCID: 2A0D09900CFE1C6BD95-807E
6 Faults Found:

00532 - Supply Voltage B+
            002 - Lower Limit Exceeded - Intermittent
             Freeze Frame:
                    Fault Status: 00100010
                    Fault Priority: 3
                    Fault Frequency: 2
                    Reset counter: 139
                    Time Indication: 0

00446 - Function Limitation due to Under-Voltage
            002 - Lower Limit Exceeded - Intermittent
             Freeze Frame:
                    Fault Status: 00100010
                    Fault Priority: 6
                    Fault Frequency: 8
                    Reset counter: 139
                    Mileage: 30779 km
                    Time Indication: 0
                    Date: 2049.14.06
                    Time: 00:08:09

00978 - Lamp for Low Beam; Left (M29)
            010 - Open or Short to Plus - Intermittent
             Freeze Frame:
                    Fault Status: 00101010
                    Fault Priority: 3
                    Fault Frequency: 146
                    Reset counter: 157
                    Mileage: 30866 km
                    Time Indication: 0
                    Date: 2050.14.19
                    Time: 15:00:51

00979 - Lamp for Low Beam; Right (M31)
            010 - Open or Short to Plus - Intermittent
             Freeze Frame:
                    Fault Status: 00101010
                    Fault Priority: 3
                    Fault Frequency: 135
                    Reset counter: 157
                    Mileage: 30865 km
                    Time Indication: 0
                    Date: 2050.14.19
                    Time: 14:59:59

03641 - Output Module for LED Headlamps; Right
            012 - Electrical Fault in Circuit - Intermittent
             Freeze Frame:
                    Fault Status: 00101100
                    Fault Priority: 3
                    Fault Frequency: 148
                    Reset counter: 157
                    Mileage: 30865 km
                    Time Indication: 0
                    Date: 2050.14.19
                    Time: 15:00:00

03645 - Output Module for LED Headlamps; Left
            012 - Electrical Fault in Circuit - Intermittent
             Freeze Frame:
                    Fault Status: 00101100
                    Fault Priority: 3
                    Fault Frequency: 139
                    Reset counter: 157
                    Mileage: 30866 km
                    Time Indication: 0
                    Date: 2050.14.19
                    Time: 15:00:53

Any help appreciated, a quick google mentioned possibly a coding issue but some pointers would be good.

Cheers

 

[The Bear78]

My Immediate thought would be a broken wire or a corroded plug. Something is breaking down, probably with vibrations from driving which is eventually triggering the bulb out warning. Resetting it will clear.the fault but then the next "intermittent" open circuit and on it comes.
Have a look at all the easy wiring and plugs in the engine bay first. It could be obvious...

I would say that a coding issue, while not unheard of would be pretty rare if they are indeed factory fitted.

 

[mmi]

a coding issue but some pointers would be good.

Hmmm... the coding is not factory coding for OEM LEDs - it's coded for Bi-Xenon headlights!
Byte 18 should be 73 for OEM LEDs front and rear, 72 for LEDs front only.
Anyways, quite interesting if it has been working fine this far.... I would look for wiring problem.

 

[RobJH]

It's a recent purchase and had only been driven in daylight previous to the fault showing itself now the nights have drawn in.
Looks like getting it booked in is the best for this one.

 

[Pauly]

PM me your vin number

 

[RobJH]

PM me your vin number

Done

 

[Pauly]

Just checked the spec against the VIN and it is definitely factory fitted LED headlights
Its actually looks like a really well specced van with powered doors, ACC, DSG, HBA etc

 

[Pauly]

Does sound liek someone may have messed with the coding ??

 

[RobJH]

It's booked in now with Bellmans auto electrical, hopefully they will get to the bottom of it sharpish.

 

[Pauly]

Bellmans are top notch on the coding and modding front so think thats a good shout

 

[RobJH]

Just an update, Bellmans took a look, faulty dipped beam modules on both sides and faulty LED driver modules both sides.
The LED driver modules come partially coded so it will need to go to VW for diagnostics first and then to have the modules coded as per the Vin.

Expensive bill coming up.

 

[Pauly]

All modules are available and are a straight swap if you have the correct part numbers

From memory you are looking around £120 + vat per module, you could just buy them and swap yourself its not that difficult, VW will charge you the price of a couple of modules just to do a diagnosis and plug it in etc ?

 

[RobJH]

Bellmans were quite adamant that it would need to be done at VW (the coding), apparently there are only 3 VAG group LED lights he can't code and this being one of them.

£120+VAT for VW diagnosis. Apparently the modules are just short of £200 each plus vat.

I could always call TPS tomorrow and see what they quote.

 

[Pauly]

This is using your vin number to fetch parts info (VIN number will need to be supplied when ordering)

Price shown is full RRP + VAT
So you would be looking at
£139 x 2 + vat = £334.58
£128 x 2 + vat = £307.63

 

[RobJH]

Thanks for that, not as bad as I was told then. Going to try the goodwill route if it actually does require all 4.

 

[RobJH]

An update, VW wasted an hour of time on it and said they couldn't get it to fault. This was when the lights weren't in auto.

The problem is, it does it in both auto and manual mode. They said they would need four more hours to look further into the modules but that is not an option.

Their opinion is that it's the screen as it's not genuine and it is affecting the sensor. That doesn't explain why the lights flash individually.
I'm not sure they even read the codes.

So, next plan - I have another van (2016) with genuine vw leds. Am I going to encounter coding issues if I swap the complete units over?

 

[Pauly]

I would say no should be fine

 

[RobJH]

A further update, headlights swapped over, everything seemed to be fine. I couldn't get them to fault but tonight they have shown to do exactly the same.
So, I'm ruling out the lights or modules.

I can see this is not going to be easy to pinpoint. Thinking possibly dry joint somewhere in the loom as suggested earlier. It seems very strange that they drop out individually. As a start i'm thinking power but possibly earth. Any clues on where to start would be great. I'm booking it in with my auto electrician so would be good to give him some pointers if possible.

 

[JimbobT6]

Hi, did you get anywhere with this in the end?
I have exactly the same issue on my 2019 T6.
Near side dipped beam (LED) intermittently working with dash warning light.

I’ve tried checking the main loom connection but nothing obvious there and rest of headlight functions perfectly.

Thanks