| 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. |
Circuit Description
The Variable Valve Timing (VVT) system controls intake valve timing in response to driving conditions. Electronic Control Module (ECM) controls Variable Valve Timing (VVT) Oil Control Valve (OCV) to ensure correct valve timing. VVT OCV is located on timing chain side of cylinder head, next to intake manifold. Oil pressure controlled by the VVT OCV is supplied to the VVT controller. VVT controller then changes relative position between camshaft and crankshaft. VVT controller is located on the front of intake camshaft. DTC P1349 is set if ECM detects valve timing does not change (fixed timing). Possible causes are
- Incorrect valve timing.
- Defective Variable Valve Timing (VVT) Oil Control Valve (OCV).
- Defective VVT controller assembly.
- 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.