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Fuel Gauge: Prizm

  1. Unplug fuel tank sending unit connector. Turn ignition on. If fuel gauge reads empty, go to next step. If gauge does not read empty, check fuel gauge wiring circuit for short to ground and/or replace gauge. See appropriate chassis wiring diagram in the WIRING DIAGRAMS  section.
  2. Connect test light between Yellow/Red lead wire of sending unit connector and ground. Turn ignition on. Test light should flash dimly and fuel gauge pointer should move toward full.
  3. If gauge operation is not as described in step 2), remove instrument cluster. See INSTRUMENT CLUSTER  under REMOVAL & INSTALLATION. Ensure all electrical connectors are unplugged from rear of cluster. Using ohmmeter, measure resistance between terminals "C" and "D" on rear of cluster. See Fig 1 . Resistance should be 55 ohms. If resistance reading is not as specified, replace fuel gauge.
Fig 1: Testing Fuel Gauge Resistance (Prizm)
G91B01811Courtesy of GENERAL MOTORS CORP.