ToreB

Hi folks, I just got hold of a Bosch hammer. But, it's only got the 19-pin, and not the OBD2-style harness.

I could need the wiring schematic for the OBD2 to 8-pin Amphenol connector, I got the hardware needed.
Could anyone with such a cable measure it with an ohmmeter?
Thanks in advance, and cheers from
Tore

IXLR8

Tore, would this help? I found this a long time ago and saved it to my HD...

ToreB

Thanks for the prompt answer Alex. :-)
I've got this too, this is the pinout for the 19-pin OBD connector used in 964 and early 993's.
The OBD2-style 993's got an extra K line, (K') and I don't know which pin this is on the Amphenol connector.
Cheers,
Tore

geolab

Hello, something tells me this is a flashback. I think we had this discussion a few years ago ? Tore , Alex, and the best in this, Loren.
The cables are confusing.
Which exact cable you need the diagram for?

Something confuses me since years back with the cables diagrams
On the PST2 out, there is a 20 pin connector.
With the pst2, there are three kinds of cables.

One connector is for the 20 pin on PST2 and 8 pin (and ground) Amphenol from other side (adaptor).

Then there is 8 pin female Amphenol to 19 pin Amphenol
Then there is 8 pin Amphenol to 16 pin OBD2
Then there is 20 pin on PST2 direct to 16 pin OBD2.

If we want to hook the PST2 to OBD2 socket with the above cables, we have two choices

So either 20 pin socket to 8 pin Amphenol male- 8 pin Amphenol female to 16 pin OBD2
Or 20 pin PST2 socket direct to 16 pin OBD2 cable.

If we check diagram for these two setups on ohmmeter, there is one pin different at the end
On PST2-Amphenol adapter-OBD2 (pin 9 is wired 12v) (looking at the pins facing socket)
On PST2 cable to OBD2 cable (wire to pin 9 is on pin 1) (cable number 00072195885)

What confuses me is that both cables are original and both work, anyway.

Tore, what I understand is you need above Amphenol diag to OBD ?
OBD cable socket facing you (looking at the pins)
\01-02-03-04-05-06-07-08/
\9-10-11-12-13-14-15-16/

above Amphenol diag. to OBD
7 - 10
8 - 2+6
10 - 4+5
12 - 9
13 - 8
14 - 16
19 - 14

regards

ToreB

Hey, geolab, thanks!
I apologize for any fuzziness in my initial post.
I need the 8-pin female Amphenol to OBD2 cable wiring. The KTS 301 has a 8-pin male Amphenol for the OBD connection. (it's also got another Amphenol output, I guess it's the serial printer port)
This is the start of a connection diagram, 8-pin female Amphenol to 16-pin OBD2 male:
1 -
2 -
3 - 15 (L)
4 - 4+5 (GND)
5 - 16 (+12V, terminal 15)
6 -
7 - 7 (K)
8 -
Notes:
The pin numbers are normally printed on both connectors, so the pin layout info is not that important.
OBD2 pin 3 (K'-wire) must be connected, it's needed in '95 OBD2-style 993's.
OBD2 pin 11 is the knock pulse, I would think this must be connected too, but not essential for OBD quieries.
I' afraid there's internal circuitry in the KTS301 OBD2 cable harness that ebanle selection between K and K' wires, but I haven't been able to confirm this.
My information source on this is the pdf Interface details part 2, it's a cutout from the 993 service manual. See this link.

Thanks in advance, and cheers,
Tore

geolab

What I just did was with an ohmmeter, checked the diagram on the pins of the socket.
You are talking the same thing, but it seems you are pointing out the pins on the back of the socket, like on the documents, they are showing the car socket, I was talking about the cable socket
So if from the back of the socket, it woud be:

\01-02-03-04-05-06-07-08/
\9-10-11-12-13-14-15-16/

19 Amphenol diag. to OBD
7 - 15
8 - 7+3
10 - 4+5
12 - 16
13 - 1
14 - 9
19 - 11

Now if you have the 8 pin Amphenol cable to 19 pin Amphenol , by above deduction with your ohmmeter, you have the 8 pin Amphenol to OBD2 16 pin
voila

ToreB

Thanks for the emphasis. I'll inspect the my 19-pin cable later today.
Cheers,
Tore

geolab

Thank you Tore, keep us posted.

ToreB

I've now inspected my hammer 19-pin harness, it does contain some electronics for a special feedback line to the hammer. There are a handful of diodes and a couple of transistors that's connected to pin 15 (check engine control) and pin 1 (airbag gong relay) in the 19-pin connector. These are present in the 964, but only pin 15 (malfunction indicator lamp) is implemented in the early 1995 993.
However, these are not needed for the OBD2 harness, as they are only used with the 19-pin connectors. The electronics involved can therefore be ignored in this.
Here's a schematic/ pinout for the hammer OBD harness: 8-pin Amphenol female to 16-pin male OBD2 connectors.

EDIT: This connection diagram is now tested OK in 993.

Amp- OBD2
1 - 9 (rev.counter pulse/ TN signal)
2 - 16 (permanent +12V, Term30)
3 - 15 (L)
4 - 4+5 (GND)
5 - 1 (switched +12V, terminal 15)
6 - NC (unused CE light feedback line)
7 - 7,3 (K and K' lines tied together) (K' line only in 1995/2 models)
8 - 11 (knocking pulse)

All pin numbers are normally printed on the connectors, and the numbers are the same seen from both ends of the assembly.
I'm waiting for my Amphenol connector to arrive, and I'll be ready for testing this. Thanks to Alex and geolab for the vital information.
Enjoy!

Cheers,
Tore

geolab

great news.
Which amphenol you are waiting for ? I have a few amphenol small plugs (female I think) from PST 2, I can send you one if you want.

ToreB

Great geolab, I need a 8-pin Amphenol 205838-1, here's a picture:

Cheers,
Tore

geolab

Hi Tore, I cannot see the picture because I am at work, and the firewall blocks hosted pictures.
When you upload pictures on rennlist, I could see them.
Anyway, no problem because if it is the female plug, I have them. I will send you a connector or two... please send me your address by pm. Will drop them at the post office on saturday, you should have them by monday-tuesday
best regards

ToreB

Isn't Rennlist great? Thanks a lot geolab.
I've uploaded the pic to my web server here.
PM is on it's way!
Cheers,
Tore

hodmandod

Tore
I got a cable for OBD2 made by jdsporsche a couple of years years ago for my KTS 300. He may be able to help with diagrams.
Philip

ToreB

Thanks, I've already asked John. He's probably not that interested in sharing this, it's part of his business.
However, I've figured out this myself, pin connections are given above.
Cheers,
Tore