Documenting the PN history for the C4 Central Locking Pumps

[UrS4boy]

In preparation to install a remote locking system on the 94 V8 avant (which came with key-activated central locking but no remote locking system of any type), I am checking out the C4 central locking pump part numbers and there history (as much as I can tell).

We're talking this puppy:



Item 18 here:



In the beginning there was darkness and locked doors. Then there was the central locking pump, 4A0862257.

4A0862257 = pump with control module, dropped on Feb. 28, 1992 in favour of a 4A0862257B (not sure whether there ever was a 257A)

4A0862257B = pump with control module, dropped on May 31st, in favour of a 4A0862257D.

4A0862257D = pump with control module for infrared remote "Hella" (I have two spares of these, one from a 93 UrS4 and one from a 93 100) - should be the same as the one in my 93 UrS4. - dropped on Feb. 28, 1994 in favour of a 4A0862257F.

4A0862257F = from March 1, 1994 to Feb. 28, 1996. Presumably still the infrared remote (which by the way was available in Europe even on the C4 A6 and the C4 UrS6s). Dropped on Feb. 28, 1996 in favour of a 4A0862257G.

4A0862257G = March 1, 1996 to...wait a minute...it was dropped on Feb. 28, 1996...even before it was started. So there is an issue with the date data. 4A0862257G was dropped in favour of a 4A0862257J.

4A0862257H = pump with control module (no mention of remote) "VD0". I am thinking this might be what the V8 avant has.

4A0862257J = seems to be the only replacement pump left. It now shows in the C4 parts all the way back to 1991 (Europe A 100) = pump with control module for vehicles with anti-theft system for vehicles with infrared locking system. (No mention of VDO or Hella)

Being curious/stupid, I decided to check out "257A" to see if it existed. Yes it did (but I can't find the application). 257A went to 257E at the end of May 1997. But then I am told 257E was dropped in favour of 257H on, get this, end of May, 1995. Two years earlier (ouch my brain hurts). 257H was replaced by a "257P" on April 1, 2005 along with a a 4A0971014 adapter harness. Unfortunately, I can't find the application for the 257P to figure out where this "257A" branch started.

Being even more stupid, I went down the "257C" path. It was dropped in favour of a "257A". At least we already know where that lead (nowhere).

Going back to the "257J", it seems to be a universal replacement now, not only for the C4s, but also the B3s,B4s, D11s, and early D2s. (i.e. lots of potential junk yard sources).

Checking out NAmerican PNs, "257J" for infrared remote shows up in the 1995 model year which is correct. HOWEVER, when I checked out 1996 model year USA, expecting to finally see the radio-frequency remote, I see "257J" again, infrared remote. (ANYBODY with a PN off a central locking pump from a 95.5 for me to check out?)

Finally, I stumbled upon what seems to be a change for the 1997 model year, i.e. instead of an 4A0 start for the PN, it is (8L0 as in A8, etc) (8L0862257G to be specific). That PN is described as "pump with control module for vehicles with radio controlled central locking system for vehicles with anti-theft alarm and imobiliser". I was nodding yes until the last word, "imobiliser". I didn't think any NAmerican C4s had imobilisers but now I am not sure. I can't find 8L0862257G for the NAmerican market, but I did find 8L0862257N, with the same description.

Now to tackle the wiring. (At least the one I got yesterday at a wreckers, I cut the wiring harness so I have the plugs and the wires to compart to the wiring diagrams).

Head hurts, have to go now.

[mdz]

8L0 pumps has nothing to do with immobiliser, they don't have any blocking circuit output. You can't find 8L0862257G in American market, because it's European market pump with 433,92Mhz frequency. As far as I know American market had 315 MHz pumps - 8L0862257B, 8L0862257M, 8L0862257N or some of those that has no remote option. European C4 was fitted with 8L0862257 (remote) and 8L0862257A (no remote) pumps.
Here's wiring diagram for 8L0 on C4: http://www.isham-research.co.uk/quat...IUE_Mj1997.pdf
Biggest differences between 4A0 and 8L0 is that 8L0 has two vacuum outputs (one for drivers door and fuel tank flap, second for the rest of doors), radio frequency remote instead of infra-red, it works on opposite direction (vacuum on open, pressure on close) and it has K line for diagnostics and programming options.
Can't help much with 4A0 pumps, but I have some knowledge about 8L0.

[UrS4boy]

Thanks for that info. We did get a few (70?) 1997 UrS6s in Canada (zero in the US because of the lack of OBD2). There is one local to me and I know that he can use VAG-Com to make is windows, etc. both sing and dance while chewing gum (lots of impressive options that the 4A0 control units could not do).

[Rocco]

I only hope you copied / pasted the first post

[UrS4boy]

I only hope you copied / pasted the first post

I wish. Nope that is me chasing PNs backwards and forwards, through time and space until something is replaced by a new PN before the old PN even existed.

[hunker7]

There is one local to me and I know that he can use VAG-Com to make is windows, etc. both sing and dance while chewing gum (lots of impressive options that the 4A0 control units could not do).

Is there any way of finding out what sort of stuff we can make them do? I think it would be quite interesting

[Vorsprung durch Technik]

Me too I just might have a super dooper one in my march 1997 2.8 30V??? Don't know but it's late enough.

[Vorsprung durch Technik]

Hi Dave, where is the pump situated in an estate?

Just been out and looked in the left and right lockers and the pump is not in either location.

[hunker7]

Hi Dave, where is the pump situated in an estate?

Just been out and looked in the left and right lockers and the pump is not in either location.

I am not Dave, but it's under the rear seat, by the battery in foam like material.

[Vorsprung durch Technik]

I am not Dave, but it's under the rear seat, by the battery in foam like material.

Dave will confirm what you have said i am sure but i think you might be right hunker.When i changed the battery on both C4 estates there was this heavy duty foam material next to the battery right in the corner.I will investigate.

[hunker7]

Dave will confirm what you have said i am sure but i think you might be right hunker.When i changed the battery on both C4 estates there was this heavy duty foam material next to the battery right in the corner.I will investigate.

that's the one. Just be careful when taking it out, it is easy to rip the foam, and then it won't fit properly anymore, so more sound will get out. I had to tape mine when I was putting mine back

[Vorsprung durch Technik]

Just checked it and was very carefull it comes with age

Part number i have is 8L0 862 257 and just to the side of that it had PP GF 30.
I was surprised at how many wires go into it and how big it was.

[hunker7]

Just checked it and was very carefull it comes with age

Part number i have is 8L0 862 257 and just to the side of that it had PP GF 30.
I was surprised at how many wires go into it and how big it was.

My dad always says that

See, you might be able to make windows sing and dance while chewing gum

[Vorsprung durch Technik]

It looks that way Now where's my saturday night fever album.

[UrS4boy]

Is there any way of finding out what sort of stuff we can make them do? I think it would be quite interesting

I don't think anything before the 8L0 control modules can do very much. The 4A0 modules are very limited. They will close all the windows and sunroof if you hold the key in the door lock in the locked position until everything is closed. But that is about it. No magic or tricks from them, unlike the 97 8L0 modules. So seeing as you have an UrS4 and the 8L0 modules are wired completely differently than the 4A0 modules, you will be disappointed.