Latch problem / turn signals not blinking during closing

[xmucio]

Hello,

i bought Audi A4 B8 Avant 2015' last year and i have problem from beginning with not blinking turn signals during closing car. There is no problem with opening (two blinks). Every single latch is closing and opening doors all the time without issues. I checked by VCDS that there is fault in passenger door and latch status is not changing after closing car. I have thought that micro switch in latch is broken and i replaced latch to a new one (8J1 837 016 C), but still the same. I checked cable connections by multimeter between Door Elect. Pass. (J387) module and latch. All wires has continuity. I replaced Door Elect. pass. module to a second one and transfer old coding. Nothing change. I checked also old latch by multimeter and i discovered that pins 4 and 5 are normally closed if latch is open and open if latch is closed. I checked one more time wiring between this two lines with plugged latch and it behaves exactly the same way. Do You have any other idea where could cause this issue?

--------------------------------------------------------------------------------
--------------------------------------------------------------------------------


Address 46: Central Conv. (8K0 907 064 KG) - opened

20:46:19 Group 007: Passenger Front Door
door closed Pass. door Rotary Latch Status
not oper. Pass. door Inside Lock Switch
unlocked Pass. door Latch Status
insecure Pass. door Locking Status

20:46:19 Group 006: Driver's Door
door closed Driver's Door Rotary Latch Status
not oper. Driver's Door Inside Lock Switch
unlocked Driver's Door Latch Status
insecure Driver's Door Locking Status

--------------------------------------------------------------------------------
--------------------------------------------------------------------------------


Address 46: Central Conv. (8K0 907 064 KG) - closed

20:46:42 Group 007: Passenger Front Door
door closed Pass. door Rotary Latch Status
not oper. Pass. door Inside Lock Switch
unlocked Pass. door Latch Status
insecure Pass. door Locking Status

20:46:42 Group 006: Driver's Door
door closed Driver's Door Rotary Latch Status
not oper. Driver's Door Inside Lock Switch
locked Driver's Door Latch Status
insecure Driver's Door Locking Status

--------------------------------------------------------------------------------
--------------------------------------------------------------------------------

-------------------------------------------------------------------------------
Address 52: Door Elect. Pass. (J387) Labels:. 8K0-959-792.clb
Part No SW: 8K0 959 792 R HW: 8K0 959 792 P
Component: TSG BF H02 0510
Revision: Serial number: 0000136434307
Coding: 011C03205E00410001
Work Shop Code: WSC 06325 000 00000
VCID: 4EC56E25B0D4DBAA9D7-801A

1 Fault Found:
02115 - Locking Unit for Central Locking
008 - Implausible Signal - Intermittent
Freeze Frame:
Fault Status: 01101000
Fault Priority: 3
Fault Frequency: 1
Reset counter: 76
Mileage: 143680 km
Time Indication: 0
Date: 2025.06.04
Time: 18:44:39

-------------------------------------------------------------------------------

[Smac770]

Wiring?

On the B8.5 NAR passenger door lock actuator is a 6-pin connector.

Pin 1 is unused (that's for the SAFE lock function that disables the interior door handle actuation of the latch; not a NAR thing, thankfully).
Pin 2 is the common ground for the motors.
Pin 3 is for the V57 motor that disables/enables the exterior door handle actuation of the latch.

Pin 4 is the F133 contact switch for is the latch locked
Pin 5 is the common ground for the contact switches
Pin 6 is the F3 contact switch for is the latch closed

I might have F3 and F133 backwards, but from the descriptions in the wiring diagrams document, it sounds like F3 is closed and F133 is locked.

IMG_1459 sm.jpg

So you see the gray and green posts which the motors rotate (gray for lock, green for SAFE, so green is just a dummy in our versions). When you lock the car, the gray rotates disengaging the connection of the exterior handle cable to the door latch, and closing the contact switch above it. This is the confirmation to the door control module "I'm locked". The contact switch to the left is what closes when the door latch is in the closed position, confirming to the door control module "I'm closed, I can be locked".

You'll want to test the continuity between 4 and 5 and between 6 and 5 as you close the door and then lock the door (you'll have to lock it and then unplug it to test the pins on the actuator). It's easy enough to just hold the unit connected and use a screwdriver to manually close and release the latch as if the door was being opened and closed. You'll want to see the same measurements on the actuator connector as you see on the harness connector that goes into the door control module.

actuator pin 1 > n/c
actuator pin 2 > 20-pin pin 11
actuator pin 3 > 20-pin pin 13
actuator pin 4 > 20-pin pin 6
actuator pin 5 > 20-pin pin 7
actuator pin 6 > 20-pin pin 5

Might be a broken wire or terminal crimp in the harness, etc.

[xmucio]

@Smac770, thank You for your reply. I had a lot of work last few days, but finally i managed to make a little video, which i hope will help understand the issue:

[Theiceman]

ahhh for those wondering .. does not blink when "Locking" the doors not " closing" the door.

Auto powinno zaświecić kiedy zamyknales drzwi nie kiedy zamykasz drzwi

car seems to be telling you car is not secure..there are many switches inside the door lock module.. I would completely remove the module, disassemble and check the switches a this point, or just order another module.

[xmucio]

ahhh for those wondering .. does not blink when "Locking" the doors not " closing" the door.

Auto powinno zaświecić kiedy zamyknales drzwi nie kiedy zamykasz drzwi

car seems to be telling you car is not secure..there are many switches inside the door lock module.. I would completely remove the module, disassemble and check the switches a this point, or just order another module.

I have already replaced latch for a new one and door module for a second one. Still the same issue.

[Theiceman]

I have already replaced latch for a new one and door module for a second one. Still the same issue.

so vcds still pointing at the same door ?

did you replace with same part number ?? other thing i can think of is flex point in cable in the door right where it comes out of the A pillar.

[xmucio]

so vcds still pointing at the same door ?

Yes

did you replace with same part number ??

Yes

other thing i can think of is flex point in cable in the door right where it comes out of the A pillar.

Between latch and passenger door module (J387) harness is fully visible and it is not going into a flex point. Next, between passenger door module (J387) and Convenience system central control unit (J393) two CANBUS wires (low and high) goes through a flex point. If something will be wrong with these two, i will have issues with communication and i would not be able to access J387 module in VCDS, am i right?

[Smac770]

I can't even think of retyping all that shit again. AZ cloudflare losing post text in "your token has expired" bullshit.

[Smac770]

Well, let's try this again.

1, so the J393 fails to report the status of locked for the passenger door. As such, it won't arm the alarm system because the interior is not secured. But that status information comes from the J387 itself, so better to look at the data at the J387. Block 001, field 0 is the door status bitmap:

0000 0000 <- closed and unlocked

0xxx xxxx <- B8 doesn't have soft close doors, so this should be always 0 I expect. If you slowly move the screwdriver to manually close the latch, you'll feel a soft first catch but notice the latch still registers as open. I believe this to be the soft close catch position. But without the contact switch to convey this, the control module is not aware of this transition point.

x0xx xxxx <- latch fully closed
x1xx xxxx <- latch open

xx0x xxxx <- SAFE lock disenagaged
xx1x xxxx <- SAFE lock engaged

xxx0 xxxx <- lock disengaged
xxx1 xxxx <- lock engaged

xxxx 00xx <- central locking button not operated
xxxx 10xx <- unlock button depressed
xxxx 01xx <- lock button depressed

xxxx xx00 <- key cylinder not operated
xxxx xx10 <- key cylinder turned one way
xxxx xx01 <- key cylinder turned other way (not sure which way is lock and unlock)

So our concern here is do we see the fourth bit (counting left to right) toggle from 0 to 1 on locking.

2, Poland is in Europe, not North America. Meaning SAFE might be present on the vehicle in question. I have thoughts if SAFE is involved, but no point bothering with all that if SAFE is not involved. The J387 p/n and coding have no reflection on SAFE functionality. For the door lock actuator itself, revision C later E is the with-SAFE version. And version D later F is the without-SAFE version, such as used here in NAR.

If you can't recall the door lock actuator p/ns, then look at the coding of the J393 (address 46). Byte 03 (left most byte is 00) bits 3 and 4 refer to SAFE function. For me, both bits are set (reflecting SAFE not enabled and SAFE not installed). If those bits are are not set for you, then the car should have the SAFE version of the actuator.

3, your J387 coding differs from mine in two bits: bit 4 in byte 02 and bit 4 in byte 04. The bit in byte 04 is "folding mirror installed". I don't have folding mirrors, so it's not set. I presume you have folding mirrors. But long coding helper had no information about what bit 4 in byte 02 is about. Maybe that's a B8.5 thing? I do have B8.0. I wonder what your original J387 coding was.

4, when I measured my resistances on the pins:

0.8Ω - latch open
open - latch closed

0.8Ω - lock unlocked
open - lock locked

but looking at the video, so we see I assume 0.3Ω for the reading for open (5->7) and unlocked (6->7)? Then you lock it and check 6->7, and is that 121Ω? That's not nearly enough, imo, for an "open circuit". Then you "close" the latch. 6->7 is still 121Ω, but 5->7 now appears as a true open circuit. The kind of reading I would have expected for 6->7 as well.

This is why I wonder if you have SAFE. Because in a SAFE door lock actuator, there is a contact switch for both motor arms to validate each latch lever deactivation.

There was probably more, but I smell bacon, so time to go.

[xmucio]

Well, let's try this again.
If you can't recall the door lock actuator p/ns, then look at the coding of the J393 (address 46). Byte 03 (left most byte is 00) bits 3 and 4 refer to SAFE function. For me, both bits are set (reflecting SAFE not enabled and SAFE not installed). If those bits are are not set for you, then the car should have the SAFE version of the actuator.

Well, let's try this again.
3, your J387 coding differs from mine in two bits: bit 4 in byte 02 and bit 4 in byte 04. The bit in byte 04 is "folding mirror installed". I don't have folding mirrors, so it's not set. I presume you have folding mirrors. But long coding helper had no information about what bit 4 in byte 02 is about. Maybe that's a B8.5 thing? I do have B8.0. I wonder what your original J387 coding was.

Well, let's try this again.

1, so the J393 fails to report the status of locked for the passenger door. As such, it won't arm the alarm system because the interior is not secured. But that status information comes from the J387 itself, so better to look at the data at the J387. Block 001, field 0 is the door status bitmap:

0000 0000 <- closed and unlocked

0xxx xxxx <- B8 doesn't have soft close doors, so this should be always 0 I expect. If you slowly move the screwdriver to manually close the latch, you'll feel a soft first catch but notice the latch still registers as open. I believe this to be the soft close catch position. But without the contact switch to convey this, the control module is not aware of this transition point.

x0xx xxxx <- latch fully closed
x1xx xxxx <- latch open

xx0x xxxx <- SAFE lock disenagaged
xx1x xxxx <- SAFE lock engaged

xxx0 xxxx <- lock disengaged
xxx1 xxxx <- lock engaged

xxxx 00xx <- central locking button not operated
xxxx 10xx <- unlock button depressed
xxxx 01xx <- lock button depressed

xxxx xx00 <- key cylinder not operated
xxxx xx10 <- key cylinder turned one way
xxxx xx01 <- key cylinder turned other way (not sure which way is lock and unlock)

So our concern here is do we see the fourth bit (counting left to right) toggle from 0 to 1 on locking.

As i expected, locking and unlocking doesn't change bit. Opening and closing works fine.



Adres 52: Elektr.drzwi pas. (8K0 959 792 R) - opened door

22:01:29 Grupa 001: General
01000000 Door Status
00000000 Button Status
00000011 Voltages and Databus Status
12.60 V Supply Voltage

--------------------------------------------------------------------------------
--------------------------------------------------------------------------------


Adres 52: Elektr.drzwi pas. (8K0 959 792 R) - closed door

22:01:46 Grupa 001: General
00000000 Door Status
00000000 Button Status
00000011 Voltages and Databus Status
12.60 V Supply Voltage

2, Poland is in Europe, not North America. Meaning SAFE might be present on the vehicle in question. I have thoughts if SAFE is involved, but no point bothering with all that if SAFE is not involved. The J387 p/n and coding have no reflection on SAFE functionality. For the door lock actuator itself, revision C later E is the with-SAFE version. And version D later F is the without-SAFE version, such as used here in NAR.

4, when I measured my resistances on the pins:

0.8Ω - latch open
open - latch closed

0.8Ω - lock unlocked
open - lock locked

but looking at the video, so we see I assume 0.3Ω for the reading for open (5->7) and unlocked (6->7)? Then you lock it and check 6->7, and is that 121Ω? That's not nearly enough, imo, for an "open circuit". Then you "close" the latch. 6->7 is still 121Ω, but 5->7 now appears as a true open circuit. The kind of reading I would have expected for 6->7 as well.

I measured old latch directly (not connected) and i had very similar resistance like in the new one. So i thought that it is correct. Maybe i will try to remove 20-pin pin 6 wire and check if problem will be solved. And it seems that i have wrong version of the latch, i have revision C/E with SAFE and it looks like i should buy revision F without SAFE. I think that this is the issue. I didn't know, because latch was wrong when i bought the car.

Smac770, thank You very much for your help. I really appreciate it. You rock!

[Theiceman]

As i expected, locking and unlocking doesn't change bit. Opening and closing works fine.



Adres 52: Elektr.drzwi pas. (8K0 959 792 R) - opened door

22:01:29 Grupa 001: General
01000000 Door Status
00000000 Button Status
00000011 Voltages and Databus Status
12.60 V Supply Voltage

--------------------------------------------------------------------------------
--------------------------------------------------------------------------------


Adres 52: Elektr.drzwi pas. (8K0 959 792 R) - closed door

22:01:46 Grupa 001: General
00000000 Door Status
00000000 Button Status
00000011 Voltages and Databus Status
12.60 V Supply Voltage



I measured old latch directly (not connected) and i had very similar resistance like in the new one. So i thought that it is correct. Maybe i will try to remove 20-pin pin 6 wire and check if problem will be solved. And it seems that i have wrong version of the latch, i have revision C/E with SAFE and it looks like i should buy revision F without SAFE. I think that this is the issue. I didn't know, because latch was wrong when i bought the car.

Smac770, thank You very much for your help. I really appreciate it. You rock!

you can often tell by the number of pins coming out of the connector.. you can look up the OE part number on line and look for a pic and count the pins.. then compare to your.