Fuel Gauge Circuit Test (Sienna, Tacoma & 4Runner)

Disconnect fuel tank sending unit connector. Turn ignition switch to ON position. If fuel gauge indicates EMPTY, go to next step. If fuel gauge does not indicate EMPTY, repair short in wiring harness. See WIRING DIAGRAMS .
Connect a 12-volt, 3.4-watt test light between terminals No. 2 and 3 of sending unit wiring harness connector. See Fig 1 and Fig 2 .
With ignition switch in ON position, test light should be on and gauge needle should move toward FULL. If test light is not on and gauge needle does not move, check wiring harness for open. Repair as necessary. If wiring harness is okay, perform FUEL GAUGE RESISTANCE TEST .

Fig 1: Identifying Fuel Sending Unit Harness Connector Terminals (Land Cruiser, RAV4 - Main Unit, Sienna, Tacoma & 4Runner)

Fig 2: Identifying Fuel Sending Unit Harness Connector Terminals (RAV4 - Sub Unit)