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Home >> Toyota >> 2004 >> Matrix Base, FWD, Automatic >> Repair and Diagnosis >> External Pages >> Different car >> Section 33 (Engine Controls - Self-Diagnostics) >> Diagnostic Tests >> DTC P1656 Or DTC P1663 >> Circuit Description
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Circuit Description

WARNING: This page is about a different car, the 2002 Lexus ES 300. However, it is still accessible from the selected car via links, so may be relevant.

The Variable Valve Timing (VVT) system controls intake valve timing in response to driving conditions. Electronic Control Module (ECM) controls Oil Control Valve (OCV) to ensure correct valve timing. DTC P1656 or P1663 is set if ECM detects an open or short in OCV circuit. DTC P1656 is for bank No. 1 (right cylinder head) OCV circuit. DTC P1663 is for bank No. 2 (left cylinder head) OCV circuit. Possible causes are: