Diagnostic Aids

After confirming DTC P0121, use Toyota hand-held tester or scan tool to access CURRENT DATA to confirm throttle valve opening percentage with throttle open and closed. 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 8-20 percent, VTA2 circuit may be open or shorted. If percentage displayed is always 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.