Mk4 golf tailgate lock problem

[sandancer]

Hi, After resolving my electric window & door central locking problem (blown fuse) the tailgate lock does not work from the remote. I've removed the interior cover to inspect, the barrel locking mechanism works fine and the solenoid manually moves. Could the problem be related to the soleniod or the sensor which I think detects that the tailgate is fully locked?
I tried to check if I am getting a feed to the soleniod whilst the tailgate is closed, but only on occasions I get a feed, and this only seems to happen after I have armed the remote locking then manually open the tailgate.

Sorry its abit long winded, but the more info the more someone may undertsand.

Cheers

[Big_E]

I'd like to know this, my Mk4 does the same, boot doesn't work on the Central locking, you have to open it manually. very annoying. There isn't even a boot catch inside for it.

[t211]

I have an interresting tailgate problem too, which might shed some light.
First - the whole lock system seems quite complicated and I'm far from sussing it all out!
I have never had a boot light. Bulb is fine. Read some stuff on UKMKIVs adn Vortex but little of great help.
Have bought a new VW part "micro switch" for boot lock, but can't see where to fit it. If i plug it in to the loose connector (car had had boot damage prior to me owning it - so reckon the 'repairers' didn't bother refitting/buying a new one) to the right of the lock system and press the micro switch the interior lights come on - so i'm guessing it now thinks boot it open. Reckon it goes some where near the actual boot catch mechanism that I can't get at til i get the correct spline tool.
However - still no boot light!
I think this is a microswitch in the catch mechanism (has a little 3ping connector plug to harness) that's corroded - sure looks it.

Do you really have no boot catch to hold the boot shut or do I misunderstand??
Does you boot light work?
Does the alarm re-arm after about 30s if you unlock remotely and just open the boot?

Hope to be of help and will post more as I learn it! Any help anyone can be with my probs - greatly appreciated!
Toby.

[sandancer]

Yes there is a boot catch and a switch fitted (which is located inside the tailgate and fitted directly on the catch).
Yes the boot light does work, which is something that will tell me if the switch works (if it goes out once the tailgate is closed).
No the alarm does not re-arm. What I mean is
1. arm the alarm.
2. wait a few seconds
3. open the tailgate using the key/lock
4. the alarm then sounds
5. close the tailgate and ocassionally get a 12v ish feed, but no mechanical movement.

I'm now thinking that the soleniod could be goosed, does anyone know if they are common failures?

Hope you have some luck solving your problem.

[neileg]

90% of electrical problems with tailgates on any make or model are down to the wiring harness where it joins the body to the tailgate. Over time the constant flexing wears or fatigues the wiring and you get shorts or open circuits as the wires move around.

The additional issue on the Golf (I think this applies to the MkIV) is that the washer tube that passes through the wiper spindle leaks and you get a constant bath for the lock mecanism.

[bora(ing) nick]

Hi, After resolving my electric window & door central locking problem (blown fuse) the tailgate lock does not work from the remote. I've removed the interior cover to inspect, the barrel locking mechanism works fine and the solenoid manually moves. Could the problem be related to the soleniod or the sensor which I think detects that the tailgate is fully locked?
I tried to check if I am getting a feed to the soleniod whilst the tailgate is closed, but only on occasions I get a feed, and this only seems to happen after I have armed the remote locking then manually open the tailgate.

Sorry its abit long winded, but the more info the more someone may undertsand.

Cheers


A friend of mine had what sounds like a similar problem. If the rest of the cars central locking worked after replacing the fuse, it's likely that the boot lock caused it to short in the first place.....

Secondly, golf iv's are renound for the rear washer hose coming away from the jet itself and getting water all over the lock / solenoid, (this may of been what caused the short) If it wasn't the washer pipe (ie if that still works) the seals around the boot may be letting water in.

From what you've said i'd replace the solenoid and hopefully that should resolve the problem.

All the best...

Nick

[Veedubber]

Hi, After resolving my electric window & door central locking problem (blown fuse) the tailgate lock does not work from the remote. I've removed the interior cover to inspect, the barrel locking mechanism works fine and the solenoid manually moves. Could the problem be related to the soleniod or the sensor which I think detects that the tailgate is fully locked?
I tried to check if I am getting a feed to the soleniod whilst the tailgate is closed, but only on occasions I get a feed, and this only seems to happen after I have armed the remote locking then manually open the tailgate.

Sorry its abit long winded, but the more info the more someone may undertsand.

Cheers

Is the key hole at a jaunty angle?

[sandancer]

The key hole is positioned at the 12 o'clock position. I am going to have another look over the week end to try and bottom this out!

Watch this space!!!

[sandancer]

Well, after an hours investigation, I've managed to find the route cause of my problem (see attached picture). Well as 'neileg' mentioned 90% of electrical faults are related to the wiring harness. I'm sure many people have come across this before, but could you let me know what was done to repair this and has it lasted long, also an approx cost. Can a samll part of the harness be replaced?
My short term solution was to crimp the broken ends together, as I thought soldering would just make the copper more brittle and fracture again.

Many thanks for everyone's help.

:biglaugh:

[neileg]

Just crimping the ends toether won't be a long term cure. The fatigue in the wires will be nearly as bad within a centimetre or so of the break. So it will go again.

You really need to cut back about 100mm on each side and replace with new wire. Soldering or crimping wil be fine. You need to use new wire as this the plastic sleeve will be more fleixble than old salvaged wire. A bit fiddly but not that hard and not expensive. Expect the repair to last at least as long as the age of the car now.

Last time I had to do a splice repair like this it was under the bonnet, in the rain, on the Edinburgh ring road. Stressed? You bet!

[johnnyjb]

Ive a Mk4 1999 and the tailgate never unlocks aswell.Ive looked at the cables entering the tailgate and thers only one brown cable looks like 1.5mm squared cable should i have neutral aswell.Could the neutral be comin down from the electric wiper which is just above the lock.Could anybody tell me how to carefully remove the plastic interior panel,i have the bottom part off but the top by the window is more sturdy and i dont wanna rough it out

[sandancer]

Hi,
There should be 3 wires (1 heavy brown 3mm wire, 1 small yellow 1.5mm wire & 1 small blue 1.5mm wire) The brown is a neutral for the rear heated screen (i think) and the yellow and blue are for the boot soliniod, which actuates with the central locking. You clearly need to find both ends and i would recommend inserting a 100mm length of cable between the broken ends, this will help prevent the cable from failing again.

The top half of the pastic trim does just pull off, just try to be careful in which direction you unclip it. Do not use big screw drivers to prise off, as you may slip and damage the heated screen element or worse smash the rear window.
Good luck.

[johnnyjb]

HI i took pictures of the cables is this ok its a bit unclear but couldnt get the cables in a proper position and take the pic at the same time

[sandancer]

Picture 1281 looks like the side (looking at the tailgate top right hand side) but there appears to be the solinoid wires missing, unless on the earlier models VW had the wire coming through the LHS. Best way to find out would be to remove the tailgate cover to expose the lock mechanism. The cover is just clipped on appart from 2 screws located in the handle grip pockets.
Check what colour the wires are coming from the solionid then trace which side of the tailgate the enter the car shell.
While you have the cover off, check what the other guys have suggested earlier (water from the rear wash wipe, etc).

You'll get there in the end and feel better you've fixed it yourself!