Here’s a diagnostic situation that can sometimes lead us around in circles. On a 2001 Lexus RX300 AWD, we had a DTC P0500 and no speedometer operation, and the Check Engine and Vehicle Stability Control (VSC) lights were on.
Recently we had a 2001 Toyota AWD RAV4, with 114,000 miles on the odometer, come into the shop for transmission diagnosis and repair. It had a bind feeling on the 1-2 shift and a flare when it shifted to third, no codes and burnt fluid. Once it was in third and then fourth, it would drive fine, and the lockup also functioned properly.