Diagnostic Aids
WARNING: This page is about a different car, the 2002 Toyota Tundra. However, it is still accessible from the selected car via links, so may be relevant.
After confirming DTC P0120, use Toyota hand-held tester or scan tool to confirm throttle valve opening percentage with throttle fully closed and fully open to determine probable cause. If percentage displayed is always zero percent, VC circuit may be open or VTA circuit may be open or shorted. If percentage displayed is always approximately 100 percent, E2 circuit may be open. Using hand-held tester or scan tool, read FREEZE FRAME data. Freeze frame data records engine conditions when malfunction is detected.