Central Locking GT Coupe 5E 1985

[Shapster]

Just wondering if anyone can help me in my quest to reinstate central locking on my 1985 GT Coupe 5E!
When I bought the car last year the only key supplied was a basic non Audi 'Mr Minit' style copy. It didn't occur to me at the time to even think about Central locking so didn't ask the questions I could have.

But as the words 'Power Lock' are printed on the interior lock stalks, and there was still a central locking mechanism inside the drivers door when I popped off the door card to sort the window motor, I'm hoping the system can be resurrected.
But although I'm fairly practical, I'm b@ggered if I know where to start on this one!

I guess that somewhere in the bottom of a previous owners junk drawer is an electronic key / fob which would do the the trick but no hope of finding it!

So I 'm wondering if there's a way of matching a new one to the existing mechanism or will it be a case of a full new mechanism with new matching key?

Any pointers greatly appreciated!

[Sie!]

Afternoon,

Don't worry about the key, it's a vacuum system that works directly from the inner door lock... providing the key unlocks the door, it will work the central locking. When you unlock the door, the actuator inside the drivers door should activate the vacuum pump and open the rest.

Have you tried the fuses? Otherwise I would check the plumbing to the pump that's located in the boot, check the diagram on the link below;

https://audi.7zap.com/en/rdw/audi+co.../8/862-110010/

I have an 80 of the same vintage so cannot give you exact pointers, but the principle is the same.

Hope that helps,


Simon

[Hanuman]

Assuming that the earlier setup is the same as that on th ur, come 1985....

One actuator (drivers door) has an integral switch. This is the control valve.
The other door has a similar valve, but no electrical connection, and so is an operating valve.

The key turns the lock.
The various interlinking rods inside the door cause the control valve to move. The switch is made, which signals the vacuum pump, and the other door(s) unlock under vacuum control.

From inside, moving the locking button up or down on the drivers door causes the same thing to happen.


It always seemed odd to me that audi were so tight in putting only one control valve in on the B2 chassis. (The vacuum pump takes only one door locking signal, to my knowledge)

[Roger Galvin]

The central locking system is driven by an actuator positioned below the driver's door lock, so firstly having removed the door card (without breaking the door pocket) check that when the lock is activated the plunger on the actuator moves up and down. Forget the pump in the O/S rear quarter of the boot for the moment what we need to establish is whether there is power to the actuator. Unplug the actuator (3 pins) and peel back the rubber shroud, the centre wire should be red/black, this is the power wire driven from the permanent live (30 amp) circuit from the battery. Using your multimeter check that you have got 12 volts.

If you have no voltage then the balance of probabilities is that the red black wire is broken, but check the fuse anyway, the door jam is the most common place due to the repetitive flexing as the door opens and closes. Drop the trim panel under the steering wheel and remove, pull off the door seal and remove the kick panel and the spacer. This will give limited access the the wiring harness through the bellows in the door jam. Unclip the harness from the inside of the door skin and then feed it gently backwards through the bellows check the integrity of the three wires red/black (power) and green/blue and green/ red resp. being the lock/unlock control wires to the pump. Repair as required. Reassemble wiring harness to actuator and test again.

If this doesn't cure it post on here again.

[chalkyh]

Yep, vacuum system. My 5E had the same problem when I first bought it. The pump is located in the OS corner of the boot up between the washer bottle and fuel tank filler neck on a bracket and behind the boot liner. I first removed the pump and bracket together - then the vacuum / pressure hose. Sucking and blowing on the tube into the car should work the locks if the hoses, pipes and actuators are ok.

Roger's info above is good.

I've known it to be the wiring into the door where it's continually bent by the door opening.

Mine was the pump, and a Golf Mk2 one was cheap and connected up properly and worked, just a small mod on the carrier to make it bolt up as original.

[Shapster]

I'd like to say a big Thanks to you guys who've offered very useful advice to my question.
I think the most useful fact has been that the car doesn't actually have the style of key or fob which can unlock the car as you walk towards it which simplifies the problem somewhat - seems my solution is within the car itself so no excuses!
Today I've been suffering from either hay fever or the effects of a bad bottle of red last night so all I could haul my ass to do was check the fuses

Typically, all fuses are fine so next job is to start poking around in the boot and behind the drivers door card..

Thanks again guys, and will post results when I have some

[Shapster]

Quick update: since it was easier to unscrew the rear washer bottle in the boot and pull down the boot liner to view the pump (ie easier than removing the door card) I went for that option. And there was my answer: pump is missing, with a female connector plug and vacuum hose hanging loose next to it and a sealed little plastic pot: presumably a receiver of some kind.
So...the hunt is on for a replacement pump!

Thanks to ChalkyH for the tip re: possible use of Golf Mk 2 pump.
Thanks again for the tips which motivated me today

[Duffy3074]

I've got one of these to go into my B3 if you are looking to add to what's there

https://www.rclick.co.uk/product_inf...oducts_id=1136

[Shapster]

Have you tried the fuses? Otherwise I would check the plumbing to the pump that's located in the boot, check the diagram on the link below;

https://audi.7zap.com/en/rdw/audi+co.../8/862-110010/



Thanks a million for the link Sie, it's well and truly put me on the road to finding a new pump

[msh]

Originally Posted by Hanuman

It always seemed odd to me that audi were so tight in putting only one control valve in on the B2 chassis. (The vacuum pump takes only one door locking signal, to my knowledge)

Nothing special, just economy according to the standards of the day. B2 wasn't much more upmarket than mk2 golf, and golf uses essentially the same stuff. Also, two door switches requires more sophisticated pump, not just more parts, haha.