DTC P1521: Variable Resonance Induction System No. 1 (VRIS1), Open Or Short Circuit: Condition

DTC is set when Powertrain Control Module (PCM) detects open or short circuit in VRIS solenoid No. 1 system with ignition switch on. Possible causes are:

• VRIS solenoid No. 1 malfunction.
• Open or short circuit between terminal "A" on VRIS solenoid valve and main relay.
• Open or short circuit between terminal "B" on VRIS solenoid valve and terminal No. 4K on Powertrain Control Module (PCM).