Caprice Wagon RWD V6-262 4.3L (1992)
Pressure Operated Electric Divert/Switching Valve (PEDES): Description and Operation
Wiring Diagram
Air management is controlled by a switching valve and a bypass valve, each with an ECM controlled electrical solenoid valve. When the solenoid valve
is grounded by the ECM, AIR pump pressure will activate the valve and allow pump air to be directed as follows:
^ Cold Mode - The switching solenoid valve is energized which in turn opens the port valve and allows flow to the exhaust ports.
^ Warm Mode - The switching solenoid valve is de-energized and the bypass solenoid valve is energized. This closes the port valve and keeps the
converter valve seated, thus forcing flow past the converter valve and to the catalytic converter.
^ Divert Mode - Both solenoid valves are de-energized, which opens the converter valve, allowing air to take the path of lease resistance, i.e., out the
divert/relief tube to atmosphere.