| CAUTION | If Engine Control Module (ECM) replacement is instructed in following test, always ensure ECM electrical connectors and ground circuits are okay. If either are defective, repair and repeat testing to confirm ECM malfunction. On models equipped with engine immobilizer, if ECM is replaced, ECM must be programmed with proper ignition key code for engine immobilizer system. For programming procedures, see COMPUTER RELEARN PROCEDURES - TOYOTA article in GENERAL INFORMATION, or appropriate ENGINE IMMOBILIZER SYSTEMS article in ACCESSORIES & EQUIPMENT. |
Circuit Description
In this system, the signal of the stop lamp switch is used to judge whether the acceleration system is abnormal or not. The stop lamp switch has a duplex system (signals STP and ST1-) to memorize the abnormality when the signals of depressing and releasing the brake pedal are detected simultaneously. DTC is set if for more than 0.5 second or more, with ignition switch on and brake pedal is released, the STP signal is off when ST1- signal is off. Possible causes are
- Stoplight switch signal circuit is shorted.
- Defective stoplight switch.
- Defective ECM.
Diagnostic Aids
This DTC uses two-trip detection logic. Using Toyota hand-held tester or scan tool, read FREEZE FRAME data. Freeze frame data records engine conditions when malfunction is detected.