Toyota Repair: toyota transmission, throttle position sensor, speed signal

Question
In reference to your question on the 92 celica auto trans issue with third gear only unless manually shifted, I am curious what you found to be the issue. I was curious because it seems like it would be the tps, but I don't know where the trans gets the signal of the rpm.
Thanks!

Answer
I don't remember the details of that question but I'll try to answer yours. The ECM gets the engine rpm and the vehicle speed signal in an ECT(electronic controlled transmission)it also gets a signal from the throttle position sensor, all three inputs will determine up/downshift points. The ECM does this by controlling the shift solenoids based on this information.