Retrofit of facelift BCM into pre-facelift Mk7 (in progress, please help 😬)

[DV52]

....................... the turn signals doesn't works

hmm........ which turn signals (front, or rear)?

According to my BCM compare spreadsheet - it looks like someone has attempted to code US style turn-signals into the new BCM. Unfortunately - I can't understand the coding changes (they look wrong)!!

In any event, it appears that this car has incandescent turn-signal lamps in the headlight fittings (because Dimmwert AB = 100). I would caution against enabling US style turn-signals on a car that has incandescent turn-signal lamps. The turn-signal lamp bases in these cars are rated for operation of what engineers call "50% duty cycle". This is because the turn-signal only illuminates 50% of the time.

When you enable US style turn-signals, the lamp illuminates 100% of the time (in this car, when the low-beams are switched-ON). The rating equation for electrical devices says that power is proportional to the square of electrical current. So, doubling current from 50% duty cycle to 100% results in a four-fold increase in power flow!!

So, the "US style turn-signal tweak" will force 400% more power to flow through a lamp holder that was designed for 50% Duty Cycle operation - not good!!

Bottom line= while US style turn-signal is OK for LED lamps (because of the low current needs of these devices), incandescent lamp holders on the turn-signal fitting will overheat and will eventually fail

My suggestion is that you revert the channel settings with the ID numbers in my spreadsheet below back to Old Setting values. This will disable US style turn-signal - but it should resolve your turn-signal problem ( I think)

ID
729
720
733
734
718
919
910
923
908

Don

 

[Toluxo]

hmm........ which turn signals (front, or rear)?

According to my BCM compare spreadsheet - it looks like someone has attempted to code US style turn-signals into the new BCM. Unfortunately - I can't understand the coding changes (they look wrong)!!

In any event, it appears that this car has incandescent turn-signal lamps in the headlight fittings (because Dimmwert AB = 100). I would caution against enabling US style turn-signals on a car that has incandescent turn-signal lamps. The turn-signal lamp bases in these cars are rated for operation of what engineers call "50% duty cycle". This is because the turn-signal only illuminates 50% of the time.

When you enable US style turn-signals, the lamp illuminates 100% of the time (in this car, when the low-beams are switched-ON). The rating equation for electrical devices says that power is proportional to the square of electrical current. So, doubling current from 50% duty cycle to 100% results in a four-fold increase in power flow!!

So, the "US style turn-signal tweak" will force 400% more power to flow through a lamp holder that was designed for 50% Duty Cycle operation - not good!!

Bottom line= while US style turn-signal is OK for LED lamps (because of the low current needs of these devices), incandescent lamp holders on the turn-signal fitting will overheat and will eventually fail

My suggestion is that you revert the channel settings with the ID numbers in my spreadsheet below back to Old Setting values. This will disable US style turn-signal - but it should resolve your turn-signal problem ( I think)

ID
729
720
733
734
718
919
910
923
908

Don

THANK YOU VERY MUCH, my car is made for North America Market (NAR), equipped with Xenon headlamps and led taillamps, now the car open and close, have the turn signals working, close the car with the hand in the handle door, but not be opened with the hand in the door, the trunk can't be opened with the kessy in the pocket, is necessary to press the trunk open button, the fob works (lock and unlock) from a distance near to 45 ft.
The Current admap is attached here.

the 09 have this intermittent dtc's

Thursday,16,February,2023,23:07:48:25289
VCDS Version: Release 22.10.0 (x64) Running on Windows 10 x64
www.Ross-Tech.com

                Address 09: Cent. Elect.       Labels: 5Q0-937-08X-V2.clb
Control Module Part Number: 5Q0 937 085 CF    HW: 5Q0 937 085 CF
  Component and/or Version: BCM MQBAB MNA H42 0411
           Software Coding: 000000000000000000000000000000000000000000000000000000000000
            Work Shop Code: WSC 03743 444 00001
              ASAM Dataset: EV_BCMMQB 021001 (VW37)
                       ROD: EV_BCMBOSCH_021_VW27.rod
                      VCID: 7F5B0154377B5063928-802A
2 Faults Found:

202506 - Motor for Central Locking of Rear Trunk/Hatch
          B12DD 15 [009] - Open or Short to Plus
          Confirmed - Tested Since Memory Clear
             Freeze Frame:
                    Fault Status: 00000001
                    Fault Priority: 4
                    Fault Frequency: 1
                    Reset counter: 9
                    Date: 2000.00.00
                    Time: 00:00:00

                    Terminal 15 status: OFF
                    Terminal 50 status: OFF
                    CAN-Bus_aktiv: On
                    Status Bremslichtschalter (HW): OFF
                    Status Bremslichtschalter (CAN): OFF
                    OFF: operated
                    Position lamps: Not operated
                    Automatic high beam assist: Not operated
                    Low beam: Not operated
                    Parking light left: Not operated
                    Parking light right: Not operated
                    last_wakeup: no cause for fault protection
                    Voltage: 12.2 V
                    Outside temperature: 20.5 °C

233497 - Remote key 2
          B147A F1 [008] - Suppressed Opening Procedure
          Intermittent - Confirmed - Tested Since Memory Clear
             Freeze Frame:
                    Fault Status: 00000001
                    Fault Priority: 6
                    Fault Frequency: 4
                    Reset counter: 49
                    Mileage: 20039 km
                    Date: 2023.02.16
                    Time: 23:03:46

                    Terminal 15 status: OFF
                    Terminal 50 status: OFF
                    CAN-Bus_aktiv: On
                    Status Bremslichtschalter (HW): OFF
                    Status Bremslichtschalter (CAN): OFF
                    OFF: operated
                    Position lamps: Not operated
                    Automatic high beam assist: Not operated
                    Low beam: Not operated
                    Parking light left: Not operated
                    Parking light right: Not operated
                    last_wakeup: no cause for fault protection
                    Voltage: 12.3 V
                    Outside temperature: 20.5 °C

 

[DV52]

@Toluxo : I have no idea what you are saying!!! I was responding to your "turn signals doesn't work" statement and you are telling me that this (NAR) car has "Xenon headlamps and led taillamps".

It really doesn't matter what type of Main/high beam lights are installed in this car - or what type of tail-light fittings it has! None of this information has ANY impact on the type of lamps in the front turn-signal lights!!

Your latest admap confirms that the BCM still believes that 2 x front turn-signal lights are incandescent lamps. I note that the US style turn-signal function on your new admap has Dimmwert CD=50. This will ameliorate the lamp base over-heatng problem in my previous post (it restores the 50% Duty cycle design criteria).

But the repeated Blinken links Dunkelphase command on Leuchte 0 BLK VL B36-Lichtfunktion H 0 is just plain wrong!!

Don

 

[wamba16]

Hi all, who can help me
I change BCM VW golf 7 2014 5Q0937084AA to 5Q0937084DD .
Now i have 1 fault in BCM (light switch implausible signal) switch not work and The front and rear lights are on fixed.
Maybe i lost anything in adaptation but not found.

 

[Cuzoe]

Do you have automatic headlights? And what happens if you try different light switch positions?

 

[DV52]

@wamba16 : When you say "I change BCM VW golf 7 2014 5Q0937084AA to 5Q0937084DD" - how did you set-up the coding values in the new module?

I assume that the original BCM in a MY14 Golf had an active long-code string, But I suspect that the "DD" dataset version has the newer adaptation channel database without a long-code facility.

So - how did you transfer the factory-set software switch positions in long-code from the old BCM (in particular, Byte 7) into the adaptation channel values on the new BCM (in particular, the Außenlicht_uebergreifend-LDS group of channels)?

And, is the setting for Außenlicht_uebergreifend-Lichtdrehschalter (LDS) = LIN on the new module?

Don

 

[wamba16]

Do you have automatic headlights? And what happens if you try different light switch positions?

yes i have automatic headlights with Xenon;and nothing happens when i switch different position

 

[wamba16]

@wamba16 : When you say "I change BCM VW golf 7 2014 5Q0937084AA to 5Q0937084DD" - how did you set-up the coding values in the new module?

I assume that the original BCM in a MY14 Golf had an active long-code string, But I suspect that the "DD" dataset version has the newer adaptation channel database without a long-code facility.

So - how did you transfer the factory-set software switch positions in long-code from the old BCM (in particular, Byte 7) into the adaptation channel values on the new BCM (in particular, the Außenlicht_uebergreifend-LDS group of channels)?

And, is the setting for Außenlicht_uebergreifend-Lichtdrehschalter (LDS) = LIN on the new module?

Don

yes normally all coding in adaptation is correct

and Außenlicht_uebergreifend-Lichtdrehschalter (LDS) = discreet same long coding in byte 7

 

[Cuzoe]

yes i have automatic headlights with Xenon;and nothing happens when i switch different position

Do you have an auto-scan and ad-map of the old BCM? And an ad-map of the new BCM?

If yes, can you post them?

 

[wamba16]

J'espère que vous pouvez m'aider

 

[DV52]

yes normally all coding in adaptation is correct

and Außenlicht_uebergreifend-Lichtdrehschalter (LDS) = discreet same long coding in byte 7

hmm...... I don't believe that your conviction above is "correct"!! Let's try doing this another way - by going back to basics!!

The software switches that tell the BCM what type of rain-light sensor is installed ain't "long coding in byte 7" - it's actually on Byte 06, specifically on Bit 0-1.
From your admap - the long-code string on your old BCM = 00151A46C04122FB0BA44080B10C0720180A00000000
So, the highlighted Byte 06 = Hex22 = Binary 00100010.

Remembering that Binary values are read from right-to-left, Byte 06, Bit 0-1 (see highlighted digits) = hex02. This is the normal set-up for a factory installed rain-light (humidity?) sensor on MQB platform cars like a Golf mk7/mk7.5.

As shown on my table below - hex02 means LIN_REGEN_Light_SENSOR

Byte	Bit	Function	Value
06	0-1	Rain Light Sensor	Not Installed =hex00 Discrete=hex01 LIN_Rain_Sensor=hex02

Again, I repeat (tautology intentional) - try my earlier suggestion
"Außenlicht_uebergreifend-Lichtdrehschalter (LDS) = LIN on the new module?"

Don

PS: the additional matter (which we haven't discussed) for a correctly operating rain-light (humidity?) sensor is the long-code value on the device, itself. As you might be aware (and as I hope you will now agree) the sensor on this car is a LIN device meaning that it uses a single wire communication protocol. The LIN master for these messages is the BCM - so the sensor is a "slave" (in VCDS speak - it's a "subsystem" in OBD11 language) to the hex09 module. If you have further problems after implementing my proposal above - I suggest that you post-up the sensor long-code string

 

[Cuzoe]

I have to admit I'm confused by this suggestion, keeping in mind that I speak no German...

Google alleges that Außenlicht_uebergreifend-Lichtdrehschalter (LDS) translates to "Outside light General rotary light switch"

Our rotary switch uses discretes so shouldn't this value be discrete? The rain light sensor is a different matter of course, but it's not clear to me that this adaptation has anything to do with that. Wjen able to get to my computer I can look through my current ad-map to see what channels dealt with RLS.

For what it's worth I have auto headlights and this channel is set to discrete. Everything works.

 

[DV52]

@Cuzoe and @wamba16 - I think that I owe both of you an apology!! My bad! You are both correct and I have erred!! .

The channel Außenlicht_uebergreifend-Lichtdrehschalter (LDS) does indeed refer to the communication method for the actual rotary light switch.

On some MQB platform cars, like a Golf mk7, this is a dumb device with a loom containing multiple wires that terminate on the BCM and on other cars, (like an Audi A3, 8V) this is a LIN device with a single wire. I incorrectly used an A3 admap when responding!

So yes, you are both correct. The first part of my previous response about the long-code string for the old BCM was correct . These software switches from the old BCM translate to the following channel on the new BCM:

• IDE08786-ENG141985-Assistance light functions-Regen_Lichtsensor>LIN_REGEN_LICHT_SENSOR

The admap for the new BCM shows that the channel above is correctly coded
Again, my apology to you both - I had a brain-fart!!

Don
PS: I will amend my wrong advice so as not to confuse others reading this post!

 

[Cuzoe]

@DV52.. no worries over here. Can I retrofit that LIN connected switch? Pointless no doubt... but I'm looking for low hanging fruit that can be done without putting the car "down" for maintenance .

Although I suppose if I'm being honest I'm more interested in the Mk8 Golf light switch (touch buttons). It's not like I ever touch the light switch anyway. And either will require some dash modification. And the Mk8 switch has the defrost options on it, hmm?

 

[DV52]

@DV52.. no worries over here. Can I retrofit that LIN connected switch? Pointless no doubt... but I'm looking for low hanging fruit that can be done without putting the car "down" for maintenance .

Although I suppose if I'm being honest I'm more interested in the Mk8 Golf light switch (touch buttons). It's not like I ever touch the light switch anyway. And either will require some dash modification. And the Mk8 switch has the defrost options on it, hmm?

hmm........ I agree with your thinking - why would you want to change the comms method for the LDS (seems like a lot of work for very little return!)?

The same series BCM is used on a range of MQB platform cars - but I would think that whether the module supports LIN based LDS would be dependent on the dataset version (I was using 5Q0-937-084-CG for my wrong advice - so this module does support LIN based LDS)

I assume (guess really) that VAG chooses to use the LIN based device to save on the cost of copper in their Audis

As for the Mk8 version LDS - that's an entirely different matter!! Retrofitting MQB-evo platform equipment onto a MQB platform car isn't impossible - but it would have to be problematic, IMO!

Don