raycm

I followed the 964 thread
https://rennlist.com/forums/showthre...&highlight=OBD
The software they used is ScanTool 3.
I installed on my HP laptop with Windows XP Home.
I looked over a few interface circuit diagrams on the web.
Then I designed one based on parts I have. This is a minimal circuit.
Not truely RS232 but works on my PC and probably yours. The 964 thread has interface circuits that can be bought.
This setup reads the Motronic, ABS, SBS, Climate Control, Alarm in my car. See photos attached.
I''m revising this email to reflect the changes I've made in the
scantool.cfg file. The scantool.cfg has been renamed scantool.txt to allow uploading to this thread and you need to change the file to .cfg to use it.
The fault code reporting is correct. Motronic has many valid Inputs and Actual Values that I found by changing the list and validating the result. Like the Throttle pedal. Idle is <1 degree and full throttle is ~84 degrees. RPM is now correct. Temps are in degrees C to follow the Shop Manual.

This tool will tell you why your, " ", is not functioning properly, and clear the fault code from memory when asked. Such a deal.

As I've presented this works on 1995 933. I imagine it will work on the 1996 and later 993 with some tinkering.

Notes: The Motronic Inputs and Actual Values with ? seem reasonable to me.
I'll start a new thread to see if someone will validate them for us.
I haven't done anything with the other controllers Inputs or Actual Values. I do have possible names listed per the shop manual diagnostics.

Ray

MPB993

Ray,

I got similar results with the same s/w but using the same interface as used by the 964 guys. I think it would be useful to map the 993 error codes and dme inputs. I get a error 41 code using the obd1 dme but think its just a start up problem. It would be useful to map some of the measurements and error codes to be specfic to a 993. Some of the measurements seem similar to that found by the 964 guys but not all of them. Had to disable the k line led on my vagcom interface to get it to connect.

Thanks to the guys over on the 964 board to getting this s/w to work and ray for diagnosis.

BR, Mark

Porscheologist

Raycm this looks like it might be very helpful to us 95 guys. A Bosch Hammer is impossible to find and very expensive. Keep us posted on your progress.

Good work!!!

deltawedge

I'm all ears if you can make it happen through a PC. Thanks.

Sumtoc

Yes, please keep us posted. Would love to have this as well.....

MPB993

Chaps,

so far I've been able to access the following units using the same interface that the 964 guys have with some minor mods to access both K lines on my 993, basically a switch to flip from one K line to the other.

I found ABS on address 31, 9600 baud, ITR (think this is climate control) on addr 81, 4800 baud and Alarm on addr 64, 9600 baud on the pin 3 K line. The pin 7 K line is attached to the ECU which has address 16 at 9600 baud.

I've cleared some of the codes on the ITR and the ecu.

Still looking for addresses for other units so if anyone knows what they are we can try and see if we can access them.

Also most of the measurements shown on the 964 work on my RoW 95 obd1 993.

BR, Mark.

raycm

I edited the original message at the beginning of this thread. That didn't change the date. Sooo I'm adding this message at the end of the thread so the thread will show up today 05/16/2006.

Ray

Sumtoc

So if I understand it this consists of 3 parts, the Scan Tool SW, the Txt file and the interface as shown in your circuit diagram? If so, we have access to all but the interface. Would you be able to build that for us? Certainly willing to pay ya for your time and the materials.....

993c2cab

I have no idea what you guys are talking about, but it sounds good. Anybody with me??

MPB993

Hello,

This tool is used to read codes off the various units within the car. To do this up until now has required a hammer which are very expensive. OBD2 readers do not work with OBD1 units within early 993s and 964s. This tool is a software item plus a small interface which interfaces to obd1 cars. It doesn't do as much as a hammer but for simple diy fault diagnosis it is very useful.

A standard VAG-COM interface board that connections between the obd connector and the pc as described on the 964 board can be made to work as well and this can be purchased off the shelf. Worth a look over on the 964 board.

BR, Mark.

tj90

Is the interface just a bread board following the schematic???? If not, I may be able to help turn the breadboard into a real circuit and get it fabbed and stuffed at a quick turn shop.... We could sell the boards on rennlist to recover the costs.
Has anyone on the board already suggested this????
We could make it as fancy as we want - even fab a box with a pseudo Bosch Hammer sticker - we could say something like "Bocsh Hamer"!!!!

cowtown

raycm, what a great post! I've read through your update a couple times, and I think you're saying that you can clear codes but not get all the value readouts yet, correct? Is it just a matter of getting the cfg setup correctly?

I'm going to throw together your circuit over the next couple weeks and give it a shot. Thanks, and please keep updating!

Colin

brucec59

Would this allow me to clear that stupid airbag light?!?

jimq

It should. I cleared other codes from my 964 with it and only one came back on.
It has a clear code button on the airbag test

John H

I have no idea what you guys are talking about. Are you saying I can buy a cable for my laptop, download the software and that would let me see and clear codes off my car's DME?

BTW, I am tech savvy