Fuel Gauge Circuit Test

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

Fig 1: Fuel Sending Unit Wiring Harness Connector Terminals