S60 L5-2.4L VIN 64 B5244S6 (2003)
Variable Valve Timing Actuator: Description and Operation
Camshaft Reset Valve
Camshaft Reset Valve (Continuous Variable Valve Timing (CVVT))
The camshaft reset valve controls the oil flow to the continuous variable valve timing (CVVT) unit.
The valve consists of an electro-magnetic valve with a spring-loaded piston. There are slits in the piston which channel the engine lubricating oil to
different channels in the continuous variable valve timing (CVVT) unit by moving the piston in the reset valve. The continuous variable valve timing
(CVVT) unit turns the camshaft (the cam timing changes). The direction in which the camshaft turns depends on the chamber in the CVVT unit which is
supplied with oil (pressure).
See also: Function
The system relay supplies the reset valve with voltage. The valve is grounded (control stage) in the engine control module (ECM). When the valve is
grounded using a pulse width modulation (PWM) signal, the oil flow in the valve can be regulated to the different chambers in the continuous variable
valve timing (CVVT) unit at variable rates. This allows the cam timing to be changed precisely and steplessly.
The engine control module (ECM) has diagnostics for the reset valve. The value of the reset valve can be read using VADIS/VIDA.
The valve is on the cylinder head above the camshaft with CVVT (certain markets have CVVT on both the intake and exhaust camshafts).
