Relief Solenoid Valve Signal Check
- Warm engine to normal operating temperature. Connect tachometer to engine. Connect voltmeter to relief solenoid valve connector terminals. Disconnect connector from throttle sensor and connect a jumper wire between terminals "A" and "C" of connector. See Fig 1.
- Start engine and increase engine speed. Current should flow to relief solenoid valve connector when engine speed is 3600-4400 RPM. Set engine speed at 2000 RPM. Disconnect No. 2 water temperature switch (located on radiator) electrical connector. Slowly decrease engine speed from 2000 RPM and watch voltmeter. Current should stop flowing to relief solenoid valve when engine speed is 1000-1200 RPM. Decrease engine speed to idle.
- Remove jumper wire from throttle sensor connector and reconnect throttle sensor connector. Slowly increase engine speed from idle (with throttle) and watch voltmeter. Current should not flow to relief solenoid valve at any speed. Quickly accelerate engine; current should flow to valve. Reconnect No. 2 water temperature switch connector.
- Disconnect electrical connector from No. 1 water temperature switch (located behind alternator) and connect a jumper wire between both terminals of connector. Fully pull out choke knob; current should flow to relief solenoid valve. Push choke knob back in.
- Remove passenger seat and fold back carpeting to expose heat hazard sensor wiring. Disconnect heat hazard sensor connector; current should flow to relief solenoid valve at any engine speed. Remove jumper wire from No. 1 water switch and reconnect connector. Reconnect heat hazard sensor. If relief solenoid valve does not operate as outlined, check heat hazard sensor and retest relief solenoid valve.
Courtesy of MAZDA MOTORS CORP.