2004 Toyota Sienna Fan

Check the fan relay(s) under the hood in the power distribution center. And the fan switch on the engine block. COOLING FAN RELAY Cooling Fan Relay 1. Disconnect negative battery cable. Remove cooling fan relay from fuse/relay box. See COMPONENT LOCATIONS . Using an ohmmeter, check for continuity between relay terminals No. 1 and 2. See Fig. 3 . If no continuity exists, replace relay. Using an ohmmeter, check for continuity between relay terminals No. 3 and 5. See Fig. 3 . If continuity exists, replace relay. 2. To check relay operation, connect positive battery voltage to terminal No. 1 and ground to terminal No. 2. Check that continuity exists between relay terminals No. 3 and 5. If no continuity exists, replace relay. Reinstall cooling fan relay. Fig. 3: Identifying Terminals Of Cooling Fan Relays Courtesy of TOYOTA MOTOR SALES, U.S.A., INC. ENGINE COOLANT TEMPERATURE SENSOR 1. Drain engine coolant. Remove ECT sensor. See ECT SENSOR LOCATIONS . Place ECT sensor and thermometer into a water bath. ECT SENSOR LOCATIONS 2. Measure resistance between terminal Nos. 1 and 2. See Fig. 4 . If resistance is not as specified, replace ECT sensor. 3. Install NEW gasket on sensor, and install ECT sensor. Fill with engine coolant. Application Sensor Location Sienna On Water Outlet, Top Right Front Of Engine.