Need help with Codes on my ECU

[kev97se]

I just finished checking my codes on the ECU and got 2 codes:

4,5 ---> 4 short pulses and 5 long pulses:
(Automatic Transmission Control Unit Signal to ECU)
and
3,3 ---> 3 short pulses and 3 long pulses
(Front Left Heated O2 sensor)

I know what to do about the 02 sensor but what is the other one? Is this some kind of sensor I could replace or is my Auto in trouble?
Thanks for your feedback

[revnum9]

I had the same problem with my 97 GLE. After taking it to an extended warranty approved service and repair shop, they pushed to a Nissan dealer for service. Dealer could not find problem and trans was covers under limited powertrain, so they replaced the trans as I below 75k.