Bill Verburg

I haven't messed w/ this since last fall, but the baud rate was checked at that time and was per spec. I tried every combination I could think of to get through to the ECU. But none were successfull. Strange as there is full access to everything else. All my codes appear to be coming from the CCU.

I really want to get rid of the drive block, but don't know if I need a new DME and harness or what.

RicardoD

Guys,

Does anyone know the pinout for a 1995 993 with the 19pin connector. Not the OBDII connector, the round 19 pin one?

I can make my own 19 pin connector and have Rennlisters I promised a Scantool to and now I'm not sure if the pinout is the same for the 1995 993 as it is for the 964.

Rick GT3

Anyone knows any reliable and working link to download the Rennlist Scantool freeware?.

Thanks,
Ricardo

IainM

pdriver says that you need to connect pins 9 & 11 on the immobilizer unit to be able to get the T-OBD interface to work on the '95 993. Post here:
https://rennlist.com/forums/3462672-post247.html

Has anyone else done this?
I assume you disconnect the battery, disconnect and remove the immobilizer.
solder in a switch
reassemble
calm down the immobilizer with various button presses on battery connection.

Guess what I'm doing this weekend!

IainM

There's no pin 1 indication on the PCB, so I had a close look at traces. Both pin 9 & 10 go to either 12V or ground (probably) so no clues there. Couldn't see any traces from the relay that went to either 11 or 12.

From PDrivers pic, it looks like he soldered onto the top, outermost connector pins. I tried that and was still not able to connect to the DME through scantool, multiple attempts, multiples scenarios.

PDriver: Can you confirm the pins you shorted were on the inside or the outside of R/A connector from the topside PCB view?

PDriver

Hi, here you find the pic from the older thread. Imageshack deleted some pictures in the past.....
Pin 9 is on the upper line the most outer pin. pin 11 the third outer on the upper line. If you look inside the plastic housing (from outside the ECU) you will see the pin numbering. Note the orange signal relais on the pcb. This one makes the OBD connection of the DME on disarming the alarm ECU.

A remark to this "Workaround". The T-OBD and other interfaces I found on the web (schematics) are not fully physical OBD compatible and therefore this solution ist working or not.

Regards, PDriver

IainM

Many thanks PDriver! That really helps.

I didn't think of that third numbering convention so it's a good job I shorted my pins with a 100ohm resistor or it could have been flatbed to dealer time!

I'll check this wiring out this weekend.

IainM

Took me a while but I can confirm that this solution works. I can now access my DME using the T-ODB tool from Tore and my immobilizer still works (i.e. I can still drive the car)

Thanks all for pulling all the pieces together.