Can DIS communicate with EGS (transmission control)?

[Albert850i]

Hi, the DIS on my laptop can talk to about 15 computers in my car, but not to the EGS transmission control.
When it tries, you can hear a relay in the EGS box clicking, but no comms. Also INPA cannot find the EGS. Is this normal?
I want to diagnose the 4HP24 gearbox as the speed sensor may be faulty.

[Timm]

Yes is the short answer - as the relay can be heard I would guess the RX line from the EGS is disconnected.

[Albert850i]

Yes is the short answer -.

Yes as the answer to "Is this normal"? So DIS cannot talk to the EGS?

[Timm]

It is normal to be able to communicate with the EGS - sorry for the confusion....

[MParallel]

And with a cheap USB setup for that matter, no ADS required.

[Albert850i]

I checked the TXD and RXD wires between EGS and EKM, all OK. Other modules such as seats can be diagnosed OK, also running through the EKM (so the EKM seems fine). Finally I took the EGS module out of the car and tried to read is on my test bench, see photo. Again no communication possible, ADS nor OBD. Tried another EGS computer, same result. I tend to think that my DIS version is not compatible with the EGS computers used in the early 90's. Is that possible?
BTW the gearbox operates fine.
IMG_6800.jpg