DTC P0121: Throttle/Pedal Position Sensor/Switch "A" Circuit Range/Performance Fault: Notes
WARNING: This page is about a different car, the 2003 Lexus LS 430. However, it is still accessible from the selected car via links, so may be relevant.
NOTE:
For information on engine immobilizer system, see COMPUTERIZED ENGINE CONTROLS
in THEORY & OPERATION article.
CAUTION:
If ECM replacement is instructed in following testing, always ensure ECM harness connector and ground circuit are okay. If either are suspect, repair and repeat testing to confirm ECM malfunction. If ECM is replaced, ECM must be programmed with proper ignition key code for engine immobilizer system. For programming procedures, see COMPUTER RELEARN PROCEDURES - LEXUS
article.