I have 2012 Octavia Mk. 2 and it has a fault that has occured as follows:

 

About 2 months ago, while I was driving, I started to hear this flicking sound. I stopped and listened and recognized that it was the sound of the central locking system trying to actuate the locks of the doors. It was not the clean "GLOCK" sound that the central loking system normally makes when I lock the car with the remote but instead a sound of already locked lock trying to lock itself again. I also noticed that the KEY LOGO in the Central Locking SWITCH, located on the central pedestal panel, was flicking from orange to green and back every time it made the locking noise. When I press "OPEN" button from the Central Locking SWITCH, the problem stops and there is no flicking lock sound any more (until the doors are locked again). Every time I reach 15 km/h, the central locking automatically locks, so basically I had to disable the "automatically lock doors" option from the Maxidot.

 

Now, about few weeks ago, the car has started to lock the doors automatically whenever I press OPEN from the remote or stop the car and remove the key from the lock. So if I press OPEN from the remote and I wait for 2-30 seconds, the doors are suddenly locked. Now you MUST NOT confuse this to the regular 30 seconds auto-lock, if no doors are open. The doors lock automatically even if I have opened one door as the car would have a life of it's own. This locking is compleatly random and I do not know what causes this. I can not leave the car for a second if the keys are inside, because I might lock myself out and small children in (very dangerous). I have noticed though that the doors will not auto lock if:

1. One or more of the doors are open, or

2. They keys are still inside the ignition lock (running car has been parked but engine shut down)

 

The doors might lock, if all the doors are again closed.

 

Some things to consider:

1. Sometimes, when the front passangers door is open, the door symbol in the Maxidot indicates that the door is momentarely closed. Also the Maxidot sometimes indicates door is being open or closed eventhough it is 100% open (random and quick indications). It seems not to be showing that the door is open, if it is in fact closed.

2. No washer fluid in the boot as some topics suggest. Also the fluid wiring seems not to be leaked anywhere. No corrosion found in the boot or inside it's left side panel or the boot door.

3. All the door handles work properly when unlocked (as they should).

4. When I stop the car and pull the key off, the doors might lock and continous red light comes to the drivers door.

5. Automatic and autonomous lock-unlocklock-unlock sequence continues if the Central Locking switch is set to LOCK.

6. Remote works as it should, or at least that is what seems to be the case (I see no fault).

7. When the doors are locked as I stated in section 4 the continous and irritating open-close does not occur.

 

My theory is

 

1. Water/moist (but where)

2. Faulty door microswitch (bur where)

3. Ground error (but where)

 

Much appriciated!

 

P.S.

 

Where is the Central Convenience Module located?

Do you have the  possibility of scanning the vehicle for fault code?

21 hours ago, AVHreplica said:

Do you have the  possibility of scanning the vehicle for fault code?

I have checked fault codes but no fault is indicated.

Did you use a VAG specific fault code reader or just a generic OBDII reader?

On 28/11/2020 at 11:31, Kadn said:

1. Sometimes, when the front passangers door is open, the door symbol in the Maxidot indicates that the door is momentarely closed. Also the Maxidot sometimes indicates door is being open or closed eventhough it is 100% open (random and quick indications). It seems not to be showing that the door is open, if it is in fact closed.

 

Broken wire in the wiring loom from the body to the Passenger door in the door hinge area?

 

On 28/11/2020 at 11:31, Kadn said:

Faulty door microswitch (bur where)

 

Passenger Door?

 

Thanks, AG Falco

8 hours ago, Liger1956 said:

Did you use a VAG specific fault code reader or just a generic OBDII reader?

 

I think that my friend used a generic one.

5 hours ago, AGFalco said:

 

Broken wire in the wiring loom from the body to the Passenger door in the door hinge area?

 

 

Passenger Door?

 

Thanks, AG Falco

 

Could this cause the self-locking problem?

A generic fault code reader may not interrogate all the modules. If it is not a broken wire between the door and the body as AGFalco suggests you might want to get the car scanned using VCDS, Carista, OBDEleven, VCP or some other VAG specific code reader.

On 29/11/2020 at 16:57, AGFalco said:

 

Broken wire in the wiring loom from the body to the Passenger door in the door hinge area?

 

 

Passenger Door?

 

Thanks, AG Falco

 

The car just got be a real VAG Specific scanner in the carage. Seemed that practically every single fault related to the front passanger door was triggered. The things is that now the airbag light has also lit and there is a text "airbag error". Time at the shop is scheduled to next Thursday. They syspected broken wiring but we'll see...

Keep us posted.

 

Thanks, AG Falco

On 08/12/2020 at 22:03, AGFalco said:

Keep us posted.

 

Thanks, AG Falco

 

I took the car to the garage last Wednesday where they changed both wiring looms inside the front doors that pass trought the doors to the car body (drivers seat and passangers front seat). They said that this is common fault in VAG cars and replacing the wires should fix the problem. 600 euros, thank you (car dealer covered most).

 

It did fix the problem for few hours which after it all started again. Now the problem is so bad that the doors will lock automatically only after few seconds after I pull the key out of the ignition switch. The Airbag Fault is now off (knocking on wood), which is nice. It is also noticable that the front passanger's door light (the red one at the bottom) flashes occasionaly and Maxidot says that the door is closed (flasing between open and closed) when it is actually open (as it did also before the fix). The garage mentioned that the airbag wiring under the seats looked fine.

 

My thoughts:

1) Microswitch in the front passanger door is faulty (why it was not seen in the VSDC/VAG COM);

2) More wiring loom is need to be replaced (rear doors);

3) Moisture, because all the symptoms tend to appeare when it rains (but where). The boot and carpets are as dry as a desert.

 

VSDC/VAG COM shows no faults anymore but let's see when I took it back to the garage... My opinion is that nobody even at the garage knew what caused this fault – mearly just guessed the cause. One would still think that this has to be related to the front passanger door as the symptoms occure there (flashing door light when the door is open and clicking sound from the same door while driving central locking in locked position).

 

Sounds similar to something I found this summer on my partner's Fabia.

Locking misbehaviour, another possible cause - Skoda Fabia Mk I - BRISKODA

 

The lock unit is probably a bit different on your car, but if it is a similar solder joint failure you might be able to put the system in/out of odd states by physically thumping the door near the lock, either on the inside or outside?