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Dual THERMACTOR Air Control Solenoid Valve

The function of each valve can be determined by externally energizing valve with vacuum lines attached. See THERMACTOR AIR VALVE OPERATION  . Check resistance of each solenoid. Resistance should be between 51-108 ohms when checked at coil terminals. If the resistance is not within these values, replace solenoid.

THERMACTOR AIR VALVE OPERATION

Airflow (1) TAB Solenoid (2) TAD Solenoid
Upstream On On
Downstream On Off
By-Pass Off Off
(1) Thermactor Air By-Pass.
(2) Thermactor Air Diverter.