Fuel Gauge Circuit Test
- Check Ground Circuit - Remove instrument cluster and leave harnesses connected. Check continuity between instrument cluster harness connector terminal No. 30 (terminal No. 28, if equipped with tachometer) and ground. See Fig 1 or Fig 2 . If continuity exists, go to next step. If continuity does not exist, repair open ground circuit (Black wire).
- Check Power Source
- Turn ignition on. Measure voltage between ground and instrument cluster terminal No. 34 (terminal No. 10, if equipped with tachometer). See Fig 1
or Fig 2
. If battery voltage exists, go to next step. If battery voltage does not exist, check fusible links, ignition switch, ignition relay and ignition power circuit. See WIRING DIAGRAMS
. Also see POWER DISTRIBUTION in SYSTEM WIRING DIAGRAMS article.CAUTION: In the following step, DO NOT ground fuel gauge terminal for more than 10 seconds.
- Check Gauge Operation - Turn ignition on. Leave instrument cluster plugged in. Using a jumper wire, ground instrument cluster harness connector terminal No. 24 (terminal No. 14, if equipped with tachometer). Fuel gauge should move smoothly to full mark. If gauge operates as specified, go to next step. If gauge does not operate as specified, replace fuel gauge.
- Check Sending Unit - Check operation of fuel gauge sending unit. See FUEL GAUGE SENDING UNIT under COMPONENT TESTS. Replace sending unit if necessary. If sending unit is okay, check harness continuity between sending unit and instrument cluster. Repair as necessary.