| 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. Variable Valve Timing (VVT) sensor may also be referred to as camshaft position sensor.
Note. Bank No. 1 refers to bank which includes cylinder No. 1. Bank No. 2 refers to bank without cylinder No. 1.
Circuit Description
Variable Valve Timing (VVT) sensor consists of a signal plate and pick-up coil. Signal plate has 3 teeth and is mounted on each camshaft sprocket. VVT sensor provides feedback to ECM in order to control intake valve timing. DTC is set when ECM does not sense VVT sensor signal during cranking for 4 or more seconds. DTC is also set if ECM does not sense VVT sensor signal with engine speed at 600 RPM or more for 5 or more seconds. DTC is also set if ECM senses VVT sensor signal 5 times while crankshaft rotates 2 times. Possible causes are
- VVT sensor circuit is open or shorted.
- Defective VVT sensor.
- 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.