Asiandude

Hi everyone and happy new year!
A question about the diagnostic connector: My car is a '87 S4 (RHD auto) and I'm looking to enable diagnostics (something like the "spanner" scanner maybe). Now I know the connector for this age/model should be a rectangular 12 pin type clipped to the LH/EZK mounting plate, but it isnt there!! I've taken all the LH,EZK and ABS controllers out and looked behind the fuse panel, looked under the carpet.....no connector. Parcel shelf and glove box out....no connector wthii? The plugs for the LH and EZK have the diagnostic wires fitted so I reckon there should be a connector. Can anyone tell me where the cable for the diag connector originates from? The harnesses for the LH and EZK go through the firewall, but no sign of a spliced cable between them.
Thanks for any feedback.

John Speake

Have you checked under the hump at the side of the passenger seat ?

Is it possible that the engine cableform has been changed as some point ?

Asiandude

Hi John
I'm pretty sure the wiring is original. The car is very low mileage (only 5800 when I got it) so it hasn't much history. The previous owner was a seriously rich guy with a stable of luxury motors, the LH control failed one day so this car had to go. The dealer who bought it from him replaced the LH and a/c evaporator then along comes me. The dashboard was pulled to do the evap so I'm thinking maybe the connector is trapped somewhere. I've done a lot of basic maintenance and the car runs ok, but only ok. The hall sensor wiring looks a mess and I'm heading for a intake refresh, but some diagnostics would really help. You've sent a couple of emails to me recently btw.

Asiandude

The hump has a system controller inside....but no connector.

John Speake

OK, I recognised you..... :-)

I am sure there's someone on this list who can look at their 87 or 88 S4 will tell you exactly where the diagnostic lead sprouts from out of the wiring cableforms..

At least you know that there are wires going to those data lines on the LH and EZK.

SeanR

On my '88 its right under the EZK, had a connector cover on it.

Why am I thinking that the '87's don't have it?

jcorenman

On '87-88 cars it will be a rectangular 12-pin connector attached to the EZK mounting plate, just below the EZK-- lower/aft corner of that mounting plate. On '89 and later it got moved to the hump that John mentioned, and became a humongous 19-pin connector (with only 11 pins used).

The connections are part of the engine harness. There are two large cables and a number of small ones that are part of the engine harness that goes through the firewall. The two big cables are the EZK and LH, three (as I recall) go to the CE panel, another to the coding plug (mounted to the rear of the EZK panel), and another goes to the diagnostic connector. The wires go from the LH and EZK as far as the firewall bushing then make a "u-turn" and return to the diagnostic connector.

Now that is all for a '87-88 LHD car. Yours is a RHD, so it may be different. The brain boxes are on the cars left side, the harness goes through the firewall on the left side, and I would think that the diagnostics connector has to still be in that neighborhood... The wizards in Oz would have the answer to that.

One more issue is that I don't think the '87 EZK/LH box firmware supports the diagnostics bus. This can be fixed by swapping chips from a '88. You can get chips from John or the other ECU-repair folks, or if you have access to spare chips and a PROM-programmer then you can do that yourself.

John Speake

That's very good info Jim, thanks. The Euro RHD are as you say. I have never found a 87 car without a diagnostic 12 way connector, although some of them were well hidden.

Asiandude

Thanks for your input guys, those cables to the firewall are all id'd now (no connector) but I'll carry on searching. Have to take out the instrument pod for work on the lighting...who knows what may be behind that?

SeanR

John, are you sure? We've looked at a few '87's and can't find a connector anywhere to hook a hammer up. I did notice on a few '88's that the connector is either just below the EZK, or just behind it. Mind was located behind the EZK and on one 5 speed yesterday it was on the bottom (easy to get to, thank goodness)

I know the '87's don't have the memory EPROM but most '88's have them. I might just be stupid here so I'm looking for clarification.

john gill

some 87 s4 s do not have them , I have 2 of them here that are without them

SeanR

Glad to hear I'm not the only one. I wonder where we can tap in to the harness, or if it's prewired for it in places that some of us don't know about it.

David L. Lutz

Could someone give is a picture of the connector that is on some of the 87's?

Asiandude

Ok...now I've stopped searching! Did clean-up the CE panel area and grounds though, so a worthwhile mission anyway.
Thanks for the info.

Glenn M

My LHD 0444 vin 87 has the connector.
Glenn