My 1987 928 S4 does not have the diagnostic connector mounted under the computers in the passenger foot well. the stud for it is there, but no connector and no sign of it. Just for a sanity check, I did look under the cover between the passenger seat and door. Just in case the shop that worked on the car before I bought the car did something strange with upgrading it to a newer computer and diagnostic connector. No such luck, it's not there either.

I'm going to pull the computers out and maybe I'll get lucky and the connector will be tucked in behind them. But, if I'm not that lucky, I'll have to look at the starting point where the connector is supposed to be tied in and trace it back from there. I really hope that the previous shop didn't do something nuts like cut it off.

I thought that some of you might appreciate this kind of adventure.

 

The pre digital dash models had a different type of connector more like the 14 pin connector type of plug looks wise but for some reason I have it in my mind that the first S4's had no diagnostic capability fitted- doubtless the chaps will be able to offer more clarity in this regard.

 

The 1987 model has a rectangular 12 pin connector and the factory computers don't have the software needed to talk to them with anything available to us (Hammer, etc). In 1988 (maybe even late 1987) they updated the computers to include diagnostic software. You can update the 1987 computer to have that feature by replacing the chips, just like putting in the SharkTuner chips. The 12 pin connector is supposed to be mounted to the chassis that holds the computers. The connector should be right below the computers. The later years have a round 19 pin connector that should be located under the cover that the trunk release button is mounted to next to the passenger seat.

The WSM wiring diagram shows the diagnostic connector and the coding plug being on the 1987 with no differences noted for mid-year changes. But, it also doesn't note any mid year changes for the '86 model, either.

If they really didn't fit a 12 pin connector on early '87's, that would be a significant problem for me. But, I could resolve it by wiring in my own connector, so not the end of the world. However, I think it's supposed to be there, and the shop just didn't mount it properly when they had one of the computers rebuilt.

 

Doubtless you will get to the bottom of it! I can confirm the earlier plug is next to the computers for what little that is worth.

FYI the round 19 pin connector is located under the passenger side cover but the remote hatch release is on the driver's side- well on both my late S4 and the GTS it is [was in the case of the S4]..

 

You don't have a rear hatch release button next to the passenger seat?

 

No- could such be an option type thing? Not the kind of thing one expects to see and did not/do not have on either of my 928's.

 

could have easily been added

 

And here I thought that it was a normal 928 feature.

 

I believe the passenger side hatch release went away in 89. My 87 and 88 have it but my 90GT and 93 GTS do not and I haven't seen it on other 89+ cars either.

 

I have the passenger side hatch release button on my '91!

 

I have it on my '90 GT. I thought this was standard? is there an option code?

 

When you remove the computers it expect you will find the 12way rectangular connector has been tucked out of harm's way...

 

John, that is my sincere hope. I probably won't have a chance to pull them out for another day or two.

 

The transmission removal and re-installation delayed the removal of the computers, but I finally got around to it this morning. The connector was loose and tucked in behind the bolted in lower cover for the CE panel. I have no idea why they didn't snap it into place on the computer chassis, but at least it appears to be intact and in good shape.


Mystery solved.