1999 Lexus ES 300, Trans works perfectly on the hoist with VSC switched off, but VSC light comes on when driving on the ground and VSC switched on; then there is no overdrive or TCC and a knock sensor code comes up (#2)Must I fix the knock sensor code first before trans will work properly?? Thanks, Sam

Optional Information:
1999 Lexus ES300 3.0L

Already Tried:
Replaced left rear wheel sensor-had a code for it--gone now, still have same symptom, now a knock sensor[#2] code is present.