[John boy.]

From much searching and tips from this forum I have now fixed my central locking! Very happy now! I bought my van with the fault on so saved myself money.

Faults,

Absolutely nothing happening when the key fob was pressed even after changing the battery
Drivers door red LED not flashing and had to lock each door individually.
Only getting 5 volts from the power feed cable to the central locking module (under drivers seat)

The fault is a corroded / broken power cable (red & blue) to the central locking module under the floor matt on the drivers side due to damp build up around the join.

Process of repair,

Make sure you disconnect the earth from the battery, chock the wheels and leave vehicle in gear as you will have to disconnect the hand brake.

I have removed the passenger seats for better access and to clean all the damp from under the floor matt but can be done with passenger seats fitted.

First remove the drivers seat via the 2x 13mm nuts and 2x multi spline bolts not forgetting to disconnect the seat pressure switch underneath.

Slide off the handbrake cover off via levering the clip out from underneath and sliding forwards.

Then remove the lower section of the handbrake cover.

You will now see the handbrake mechanism and adjustment nut.

Measure the distance from the top of the nut to the top of the threads, must be the same when re fitting, mine was 11mm, if you don't have a ruler you can use a spanner that is the same distance as a guide. Remove nut and slide out handbrake cable.

Disconnect the handbrake sensor switch.

Remove central locking module from the seat base and the 4x 16mm nuts holding it in place.

Lift up the floor matt and remove the central locking module.

Un wind or carefully snip the fabric cover back aprox 12 inches.

Part way down you will come across the power cable with a black cover round it, mine just fell apart and was covered in green corrosion powder but worth taking this off too, to check.

I stripped back the wires to get bare good wire, used a bullet connector to repair the split, plugged in the module and battery earth back on to test and boom! Central locking works?! The other cable was 3 inches long and didn't go to anything so I just removed it.

I very tightly used electrical tape to re insulate and waterproof the bare wires and re assemble.
Remember to clean under the floor matt and adjust the handbrake back to the same position..

Hope this helps, any problems or if I've missed something PM me.
John boy.
A:

 

[Brian Considine]

Excellent "how to" & thanks for taking the time to post - if ever a thread should be "pinned" this is one.

 

[t4Chippy]

Excellent "how to" & thanks for taking the time to post - if ever a thread should be "pinned" this is one.

Agreed T:

 

[John boy.]

Thanks guys, just hope it helps.
Glad it's fixed now though, doing my head in useing the key and climbing over the seats!

 

[deduct]

Thanks for the 'how to'.
I am building myself up to doing this over the next couple of days as my central locking has stopped working.
The key fob flashes but nothing happens, I have to look my van with the key in the drivers side.
Hope is the same fault as yours!


Thanks

 

[John boy.]

Hi,
Yeh sounds like the same fault. Worth checking as it's quite an easy repair. If you have a soldering iron solder the clean wires together for a solid join.
If anyone needs a new central locking module box I have a brand new one that I ordered from VW Germany as thought it was this before finding the corroded wire! Typical!

 

[T4MAT]

I undid the 4 main bolts holding the front drivers seat down and tipped it back, you can then get in and solder it up.

After undoing all the tape and getting to the red/blue wire which was very green, re-soldering and putting it all back together it still doesnt work, so maybe its the door solenoid.

I need to stop buying VW's they are as bad as Mercs but not quite as bad as BMW's. Drove the new Amarok the other day, it was gutless and felt like it was made of papier mache! Waste of time!

 

[John boy.]

Hi mate,

Yeh if you don't have anything behind your seat good idea to just tilt it back,
I'd check your door solenoid but there is also more options that I have read and seem legit.

Re-start central locking module by disconnecting battery for at least 15 min,
Clear ECU faults via OBD port with a Launch or code reader,
Some aftermarket head units affect the central locking performance.

Hope you get to the bottom of it.

 

[mat roberts]

I'm confused on mine too. I have central locking working fine but not remote locking. I have flashing door LEDs, and my wire under seat is fine (12v getting to unit). Do you think I need the box you ordered from Germany?

 

[mattjenna]

So I fixed my driver's door using the chase back to green corrosion about 6 months ago. Now passenger door has stopped opening and closing. First time I fixed I didn't take out any seats just pushed driver's seat forward. This time aggggghhhhh!

I get to the two wires which are blue and red (slightly thicker ones which are in black wrapped loom and are spliced together where they meet and then connect into the other thinner blue and red wire goes to plug in box (if that makes sense). So one of the thicker wires I chase back by undoing loom and no issue stays connected within loom and good. The other thicker wire comes off in my hand and is totally corroded inside plastic covering. So I figure I'll just rejoin it inside loom and keep undoing black clothe tape-again good thicker wire keeps going as I undo clothe tape BUT, and this is my issue, I find no other broken off think blue and red wire to rejoin the one which came off in my hand-I have now taken out front seats BOTH to pull back insulation and keep chains back loom and undoing tape and nothing.

So please, I really need help in knowing what to attach the second thick blue and red wire to inside loom - just can't seem to find point where it was joined-when the good thicker wire is connected to the thinner one all the doors EXCEPT the passenger front open and close with remote so I figure the thicker one that came off is the one which controls passenger front door.

Car is now in bits so REALLY appreciate any assistance.

Thank you so much.

Matt (Sydney-Aus)

 

[John boy.]

Hi Matt,

I was really confused too as they had bothered to splice in the second wire but didn't go to anything, I too took off all the the protective tape and still films nothing, I removed the second wire and my central locking works fine so I can only assume that the wiring loom is a generic part that is used on a different model or vehicle all together, ie just not needed on the T5. I'd be inclined to check your passenger door solenoid press the button and see if you can hear working through the door card, if not strip back the plastic door card and check the connector, I'd guess that the door solenoid has packed in.

Hope that helps

 

[mattjenna]

Thanks John.

Like you I figured out that wire went NOWHERE after pulling out both seats and then undoing the loom and chasing back. Wasted 3 hours for nothing. At least I learnt how to remove seats and handbrake etc. so of some value. Funny thing is the pass. door now isn't activating at all whereas previously it would about 50% of the time open but rarely close on remote activation. Seemed to be worse in wet weather hence I thought it was the corroded wiring. I'll check the solenoid (wherever and whatever that is) and see if I can work that out.

Thanks for the help, hugely appreciated.

Matt

 

[John boy.]

Hi Matt,

The door solenoid is the electrical component that the door handle is connected to inside your door, it controls the central locking for that door and the actual lock. If you take off the door card you will see it by the door lock. Normally makes a noise when locking/unlocking.

 

[John boy.]

I'm confused on mine too. I have central locking working fine but not remote locking. I have flashing door LEDs, and my wire under seat is fine (12v getting to unit). Do you think I need the box you ordered from Germany?

Hi Matt Roberts,

Is the key fob little light flashing when you press the button? May be as simple as needing a new battery in the fob, I think there 3 volt ones.
You can always check the central locking module by disconnecting it from under the seat and the actual box will un clip so you can check the internal connectors, mine was a little corroded so I carefully used a tiny file to clean up each connector.

Hope that helps mate.

 

[mat roberts]

Hi John, thanks for the reply, yes keys light up fine, no noise or anything when press buttons. Really annoying me as I said I've checked power and wiring to box, all ok. Excuse my igronence but I'm wondering if that box is plug & play, ie if I get another will it work with my van without being plugged in (vagcom). I just don't know. And I can't get this problem off my mind, determined to sort it somehow!
So are you saying yours didn't work before you cleaned connections up, but that cured it? Will def look later, appreciate your response! T:

 

[mat roberts]

But I'm also thinking I don't hear of those boxes failing, jus got this niggle in my mind thinking its a simple connection maybe. Argh!

 

[benseabourne]

Good work John - an excellent guide!
Now just need to treat myself to a decent spanner and socket set - had every size except the 16mm and the 13mm that I needed!

 

[ickle pob]

awesome thread - my new van doesnt lock unlock on the keyfob, no lights on door, and the central locking doesnt work using the key manually either.

I've been hunting for info and found this so will be checking the module under the seat and for broken wires. The CD multi changer doesnt work either so could be signs of damp in the area.

Paul

 

[patconnell]

Thanks for all the tips, I just slid the seat to the front, cut off the webbing and crimped the 2 together again after cleaning , sweet! had been expecting a 70 or 80 euro minimum raping from the local mechanic.

 

[PrincessPunk]

Since owning my van the central locking hasn't worked! I've replaced the key fob battery and the wiring has been redone where it had corroded, the ecu under the seat however is blue/green with corrosion. I've even tried buying a mapping program but the ecu wouldn't read it. Any ideas how much a new ecu would cost or could it be something else?