Fuel Gauge Sending Unit Test
- Remove cluster bezel from instrument panel. See CLUSTER BEZEL under REMOVAL & INSTALLATION. Remove fuel gauge retaining screws. Remove fuel gauge by pulling it straight out from cluster. DO NOT turn or twist gauge when pulling on it, or damage to cluster pins will result.
- Turn ignition on. Using voltmeter, check for battery voltage at fuel gauge (B+) pin. See Fig 1 . Using ohmmeter, check for continuity to ground at fuel gauge ground pin. If voltage and ground are not present at pins, go to next step. If voltage and ground are present at proper pins, go to step 5).
- If voltage and ground are not present at pins, remove instrument cluster. See INSTRUMENT CLUSTER under REMOVAL & INSTALLATION. Check for battery voltage at instrument cluster Red connector terminal No. 9. Check for ground at instrument cluster Red connector terminal No. 14. See Fig 2 .
- If voltage and/or ground are not present at cluster harness connectors, repair wiring as necessary. If voltage and ground are present at cluster harness connectors, check cluster for bent or broken pins. If pins are okay, replace cluster printed circuit board and retest.
- Remove fuel level sending unit from tank. Using ohmmeter, check resistance of fuel level sending unit connector terminals "A" (Dark Blue wire) and "B" (Black/Light Green wire). With sending unit float to FULL position, resistance should be zero to 8 ohms.
- With sending unit float to EMPTY position, resistance should be 100-112 ohms. If resistance is as specified, go to next step. If resistance is not as specified, replace fuel level sending unit.
- Using ohmmeter, check for continuity between fuel level sending unit connector terminals "B" (Black/Light Green wire) and "C" (Light Blue/Red wire). With sending unit float in FULL position, there should be no continuity. With sending unit float in EMPTY position, there should be continuity. If continuity is as specified, go to next step. If continuity is not as specified, replace fuel level sending unit.
- Reconnect tank sending unit to harness connector. Ensure sending unit and connector are properly grounded to vehicle. Position sending unit float to FULL position. Using ohmmeter, check resistance reading at fuel sender input pin of cluster. See Fig 1 .
- Position sending unit to other positions and check resistances to match table. See FUEL GAUGE CALIBRATION table. Correct reading should be within 4 ohms of specification.
- If sending unit resistances do not match table, replace sending unit. If resistances are infinite, repair open circuit from cluster to sending unit. After ensuring sending unit resistances are satisfactory, go to next step.
- Turn ignition off. Position fuel gauge onto cluster pins and install by pushing gauge straight inward onto pins. Turn ignition on. Position fuel level sending unit to previously checked resistance positions and note position of fuel gauge after 15 seconds. If fuel gauge pointer position is not relative to sending unit position, replace fuel gauge.
FUEL GAUGE CALIBRATION
| Position | Resistance |
|---|---|
| E | 90 Ohms |
| 1/4 | 59 Ohms |
| 1/2 | 42 Ohms |
| 3/4 | 28 Ohms |
| F | 12 Ohms |