P1656 – Oil control valve (OCV) circuit

System: Engine - VVT
Dashboard light: Check engine light (MIL)
Check-engine blink code: —
Applies to: 1SZ-FE (by platform)
Description: Oil control valve (OCV) circuit
Possible causes: Trouble area: 1.Open or short in OCV circuit 2.Oil control valve 3.Engine computer (ECM)
What to check: Checking points: 1.Check OCV connector and wiring 2.Check OCV resistance
Confidence: medium (Toyota Echo 1999–2002 factory diagnostics, same XP10 platform; not confirmed on JDM 1SZ-FE)

From the factory service material. Clear the code and test-drive to confirm it returns. Search all fault codes · Common problems · Warning lights