Golf Mk4 rear door won't unlock

[CrossMouse]

I have a 1999 Golf Mk4 GTi 5 door and the rear right door will not unlock at all. I have tried the remote locking, the key and the button on the drivers door but the locking knob does not even twitch.

If you try to pull the door handle, the knob comes up with resistance but will not stay up. I believe that this is because the dead lock has not released on this door.

If you put your ear to eg the other rear door and press the unlock button once on the remote, you hear a click in the door, which I assume is the dead lock coming off. This does not happen on the right rear door.

Any help much appreciated as I simply cannot open this door at the moment.

[yankee-doo]

Hi did you ever resolve this issue ?

I am having the same problem on my MK4 Golf GTI rear door stuck, can't open from inside or outside, guess it's a new lock or solenoid ??

Regards

Nick

[CrossMouse]

It turned out to be the door control unit, which is the electonic circuit board that sits on top of the window winder mechanism. You cannot get this part separately, perversely you have to replace the electric window winder motor to get your door to open, which comes with the circuit board and plug attached to the top!

Mk4 Golfs did have random door locking and unlocking problems on models before about 2002, see this excellent article if your problem is an intermittent lock problem, which explains how to dismantle the door lock and re-solder dry joints:

http://forums.vwvortex.com/zerothread?id=1542461

However, if your problem appears to be the same as the one I had ie. no matter how many times you press the unlock button on the remote or the drivers door, or tap the door in the area of the lock, then the chances are that the door control unit has gone.

To doubly make sure, remove the door trim panel - in the rear, I had to take the back seat out and even then use a bit of brute force as I could not get to one of the retaining screws at the bottom. You can then check the voltages at the back of the plug that goes to the window winder motor.

With the ignition on, you should have +12V on the Red/Yellow and Red/White, using the brown as the 0V.

You should also have +12V between the Orange/Brown (Bus Low) and the Orange/Green (Bus High) - This is where the control signal comes in which then goes on to the motor in the door lock unit - this motor pulses back and forth in order to release the deadlock tab and unlock/lock the door.

When you press unlock, you should get brief pulses of +12V on both the lilac and blue wires which lead to the door lock motor. If you disconnect the plug from the window winder motor, you should have a low resistance reading between the lilac and blue wires, which is basically the motor coil resistance - if this is open circuit, then it is the door lock motor which is gone.

If more than one door is affected then it is most probably a simple fuse, 37 or 38.

If you still have problems then post a reply as I ended up drilling a hole in the inside of the door, to access the door lock motor - I managed to manually rotate the motor by its drive cog and release the deadlock tab. That's another story though and was at a stage when I was convinced that it was the door lock that was at fault. If you ever get to that stage, I could take photos of where to drill holes - I dismantled the opposite door and took accurate measurements before getting the black and decker out!

I even spoke to my local VW dealer who swore blind that replacing the window winder motor would not affect the door lock - when I started speaking to him about bus systems he was completely lost...

[adamss24]

It turned out to be the door control unit, which is the electonic circuit board that sits on top of the window winder mechanism. You cannot get this part separately, perversely you have to replace the electric window winder motor to get your door to open, which comes with the circuit board and plug attached to the top!

Mk4 Golfs did have random door locking and unlocking problems on models before about 2002, see this excellent article if your problem is an intermittent lock problem, which explains how to dismantle the door lock and re-solder dry joints:

http://forums.vwvortex.com/zerothread?id=1542461

However, if your problem appears to be the same as the one I had ie. no matter how many times you press the unlock button on the remote or the drivers door, or tap the door in the area of the lock, then the chances are that the door control unit has gone.

To doubly make sure, remove the door trim panel - in the rear, I had to take the back seat out and even then use a bit of brute force as I could not get to one of the retaining screws at the bottom. You can then check the voltages at the back of the plug that goes to the window winder motor.

With the ignition on, you should have +12V on the Red/Yellow and Red/White, using the brown as the 0V.

You should also have +12V between the Orange/Brown (Bus Low) and the Orange/Green (Bus High) - This is where the control signal comes in which then goes on to the motor in the door lock unit - this motor pulses back and forth in order to release the deadlock tab and unlock/lock the door.

When you press unlock, you should get brief pulses of +12V on both the lilac and blue wires which lead to the door lock motor. If you disconnect the plug from the window winder motor, you should have a low resistance reading between the lilac and blue wires, which is basically the motor coil resistance - if this is open circuit, then it is the door lock motor which is gone.

If more than one door is affected then it is most probably a simple fuse, 37 or 38.

If you still have problems then post a reply as I ended up drilling a hole in the inside of the door, to access the door lock motor - I managed to manually rotate the motor by its drive cog and release the deadlock tab. That's another story though and was at a stage when I was convinced that it was the door lock that was at fault. If you ever get to that stage, I could take photos of where to drill holes - I dismantled the opposite door and took accurate measurements before getting the black and decker out!

I even spoke to my local VW dealer who swore blind that replacing the window winder motor would not affect the door lock - when I started speaking to him about bus systems he was completely lost...
Nothing new to me ... Glad you fixed it !

[nikitransit]

Thanks everyone who has tried to help me with this problem but I think that the problem is not electrical but mechanical. Everything on the inside of the door has been removed but I cannot open the door to be able to remove the actual lock and handle! Please, any other ideas?????
thanks :confused:

[a8 tech]

Firstly dont start messing with convience can and your fault is the lock is stuck(mechanical issue )that has been around since convience was introduce on passat.You will have to smash the lock from inside the door to be able to release the lock,and then replace the lock.Big screwy big hammer.

[a8 tech]

Bit 5 Bit 4 Bit 3 Bit 2 Bit 1
Value of
bits
Central
locking
Basic status
Safe
Locked
Door unlocked
Door locked
Unlocked
Signal error, input sensors
Status error
0 Volts, 0 Volts, 0 Volts
0 Volts, 0 Volts, 5 Volts
0 Volts, 5 Volts, 0 Volts
0 Volts, 5 Volts, 5 Volts
5 Volts, 0 Volts, 0 Volts
5 Volts, 0 Volts, 5 Volts
5 Volts, 5 Volts, 0 Volts
5 Volts, 5 Volts, 5 Volts
000
001
010
011
100
101
110
111
Electric
windows
In motion
Not moving
Within range
Upper stop recognised
0 Volts, 0 Volts
0 Volts, 5 Volts
5 Volts, 0 Volts
5 Volts, 5 Volts convience can 5 volt and should only be checked via a scope s a multimeter isnt fast enough to catch it or it can be checked via measured value blocks.

[dominichep15]

Hi. This appears to be a very common problem and I had it on both of my rear doors of my 03 TDI. The good news is I've at least managed to open them today after six months in preparation for its impending MOT where it would be be a fail. As I say, this isn't a total cure as that will involve replacing the internal gubbings which will (well may!) come later.

One thing I would like to clear up and that has cost me a tenner is that there is a YouTube video which shows some bloke with a lock pick artfully slipping it in at the back of the door handle. Well I bought a set on eBay but could not physically slip it in the gap. The difference is that in my door handle there is a small metal gromet - for want of a better word - that prevents such objects being slipped in, hence the wasted tenner. https://youtu.be/MNg18qaYU9o

Now this is what did work for me at least and within a mere 10 minutes. You will need a mallet, an old towel folded to make a thick protective pad and an additional buddy - I opted for a 14 year old due to their quick and responsive gaming fingers.

Place the thick towel on the inner door panel side of the first rear handle and hit it repeatedly as hard as you dare while your friend presses/toggles the Key and Central Locking buttons very quickly on the inside of the drivers door. For me at least, hey presto! It was even quicker on the second lock. What I've also done now is to remove fuse 37 for the central locking and I will it leave it unlocked. All are welcome to my broken brollys and yellowing newspapers.

[m50yre]

I've just replaced my door lock on my passenger rear side. I found that I sat inside the car and used the unlock button on the fob and pulled the inner handle at the same time it opened. I got a new lock non oem off eBay for £17. Tried secondhand ones but they failed shortly after installation. Need any tips on replacement let me know. Took about three hours to get the blighter out but about half an hour to reinstall as I new what I was doing by then. You'll need some spline bits, halfords sell them.

[marjonz]

sorry to bump an old thread, but stumped at the problem.
I have replaced the door control module (the unit with the lock catch just behind the outside door handle).
The power locks (and electric windows), worked once after power up. But went back to not working mode after and since stayed there.
Do I also need to replace the unit that controls the electric windows? I would have thought that the door control module is separate from the electric window controls.
It seems to me that no power is going to the right rear door since both modules (door and windows) won't work. The audio is working, as well as manually locking/opening the door.


It turned out to be the door control unit, which is the electonic circuit board that sits on top of the window winder mechanism. You cannot get this part separately, perversely you have to replace the electric window winder motor to get your door to open, which comes with the circuit board and plug attached to the top!

Mk4 Golfs did have random door locking and unlocking problems on models before about 2002, see this excellent article if your problem is an intermittent lock problem, which explains how to dismantle the door lock and re-solder dry joints:

VWVortex.com - MKIV door locks explained - why you're having problems!!! :( (http://forums.vwvortex.com/zerothread?id=1542461)

However, if your problem appears to be the same as the one I had ie. no matter how many times you press the unlock button on the remote or the drivers door, or tap the door in the area of the lock, then the chances are that the door control unit has gone.

To doubly make sure, remove the door trim panel - in the rear, I had to take the back seat out and even then use a bit of brute force as I could not get to one of the retaining screws at the bottom. You can then check the voltages at the back of the plug that goes to the window winder motor.

With the ignition on, you should have +12V on the Red/Yellow and Red/White, using the brown as the 0V.

You should also have +12V between the Orange/Brown (Bus Low) and the Orange/Green (Bus High) - This is where the control signal comes in which then goes on to the motor in the door lock unit - this motor pulses back and forth in order to release the deadlock tab and unlock/lock the door.

When you press unlock, you should get brief pulses of +12V on both the lilac and blue wires which lead to the door lock motor. If you disconnect the plug from the window winder motor, you should have a low resistance reading between the lilac and blue wires, which is basically the motor coil resistance - if this is open circuit, then it is the door lock motor which is gone.

If more than one door is affected then it is most probably a simple fuse, 37 or 38.

If you still have problems then post a reply as I ended up drilling a hole in the inside of the door, to access the door lock motor - I managed to manually rotate the motor by its drive cog and release the deadlock tab. That's another story though and was at a stage when I was convinced that it was the door lock that was at fault. If you ever get to that stage, I could take photos of where to drill holes - I dismantled the opposite door and took accurate measurements before getting the black and decker out!

I even spoke to my local VW dealer who swore blind that replacing the window winder motor would not affect the door lock - when I started speaking to him about bus systems he was completely lost...

[m50yre]

I didn't need to replace the window motor but im pretty sure the lock takes power from the motor. There's a guide on here somewhere for testing the motor and also bypassing it to test the locking mechanism. I'll see if I can find it.

[marjonz]

Thanks, will have a look around too. Will post in this thread if i find it.


I didn't need to replace the window motor but im pretty sure the lock takes power from the motor. There's a guide on here somewhere for testing the motor and also bypassing it to test the locking mechanism. I'll see if I can find it.

[John94]

Hi, I'm having this problem as well the rear passenger door won't unlock and the window also won't roll down. However, the window will roll down using the driver controls. Can anyone offer me some advice? Also how do you go about getting the bottom torq screws out of the door panel without the door being open?

thanks.

[marjonz]

Hi, I'm having this problem as well the rear passenger door won't unlock and the window also won't roll down. However, the window will roll down using the driver controls. Can anyone offer me some advice? Also how do you go about getting the bottom torq screws out of the door panel without the door being open?

thanks.

Need a long screwdriver with torx bit end. Open the other door and estimate where the two screws are located, from there you have two use the screwdriver and try to wedge it between the door and door sill to feel for the torx screw. You might be able to get the door card removed, but problem after this is if the door lock is still jammed. There are star screws only accessible when the door is open.

[Jezwillmar]

Hi, sorry to hijack this old post but I'm having the dreaded read door lock issue. I've tried most of the quick fixes but it is still locked and can't be opened inside or out. I'm at the stage where the door card is off and the access panel removed you said you drilled a hole to manually open the lock?

[marjonz]

Sorry for linking to another forum, but this might help [Mk4 Golf] Opening door lock / actuator from inside the door skin - Audio, Electrics and Lighting - uk-mkivs (http://uk-mkivs.net/topic/91344-opening-door-lock-actuator-from-inside-the-door-skin/)

[marjonz]

The solution I did was trade off the Golf for a Corolla. :-P

[Jezwillmar]

Thanks. I managed to hit the the catch with a large screwdriver from the inside until it released. Got a new pattern part eBay one en route.

[Mmalkie]

I've heard that for those who can't open a door lock that the advice in this youtube video will work...

How to open a VW door that won't open from inside OR outside - YouTube (https://www.youtube.com/watch?v=Fy3KbKkAZZ0&feature=youtu.be)

Goto 2:44 & watch the whole of the remaining video from there....

[jgille30]

I have the same problem on my 03 MK4 Golf, the rear passenger side door does not unlock with the key, with the fob, with the inside handle or the outside handle but the window still opens. Previous replies have left me confused, do I need to replace the control unit (including the window mechanism) or the door lock? No amount of bashing, poking or threatening has made any difference. Is the door dead-locked for some reason? If so, is there some way to release the dead-lock?

[JadeL]

I have a Mk4 golf, my rear passenger door won't unlock and I can't open it from the inside or outside... How can I unlock the door to be able to open it please????
I have to unlock my car, from the passenger side using my key in the door.
It was working till Saturday worked fine earlier in the day and stopped working I had to get my child out through the other back door. I don't think the child lock is on as pretty sure I've opened it from the inside before. But may be wrong. Also when pulling inside handle the lock button that pops up when unlocked dosent move when pulling inside handle.
I don't have the money to pay to get it fixed right now.

[SR123]

I created this video a while back to explain another possible solution to this - it involves flicking the little plastic lever as mentioned above: How to open a VW rear door that is locked and won't open at all - YouTube (https://youtu.be/9hfggI7VT9s)