| CAUTION | If ECM replacement is instructed in following testing, always ensure ECM connectors and ground circuits are okay. If either are defective, 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 - IMPORT article in GENERAL INFORMATION, or appropriate ENGINE IMMOBILIZER SYSTEMS article in ACCESSORIES & EQUIPMENT. |
Note. For component location, see appropriate illustration in THEORY & OPERATION article.
Note. Variable Valve Timing (VVT) sensor may also be referred to as camshaft position sensor.
Circuit Description
The Variable Valve Timing (VVT) sensor consists of a signal plate and pick-up coil. The signal plate has one tooth and is mounted on each intake camshaft. The VVT sensor provides feedback to ECM in order to control intake valve timing. DTC is set when ECM detects a deviation in crankshaft position sensor and VVT sensor. Possible causes are
- Mechanical system malfunction (timing chain stretched or timing chain jumped teeth).
- Defective ECM.
Diagnostic Aids
Using Toyota hand-held tester or scan tool, read FREEZE FRAME data. Freeze frame data records engine conditions when malfunction is detected.