3-Way Solenoid Valve

Disconnect vacuum sensing tube at servo diaphragm. Disconnect intake manifold vacuum tube at solenoid valve. On 626 models, disconnect electrical connector and connect battery power as shown in Fig 1.

Fig 1: Mazda 626 Three-Way Solenoid Valve Test
Courtesy of MAZDA MOTORS CORP.
On all other models, disconnect wire which comes from engine speed switch and ground terminal as shown in Fig 2.
Turn ignition switch "ON". Blow air through hose disconnected from servo diaphragm; air should escape at solenoid filter.
Turn ignition switch "OFF" and blow through hose again; air should escape from intake manifold vacuum inlet port. If valve does not respond as outlined, replace 3-way solenoid valve.

Fig 2: Mazda B2000 & GLC 3-Way Solenoid Valve Test

Courtesy of MAZDA MOTORS CORP.