Fuel Gauge Inoperative

Conditions for Fault-Tracing:

Fuel Level/Gauge:

- Other instrument panel instruments working

Sources of Fault:
- Open-circuit in fuel level sensor.
- Open-circuit in fuel level sensor ground lead.
- Signal lead short-circuited to battery supply.
- Open-circuit in fuel level sensor signal lead.
- Fault in test signal from instrument panel.
- Fuel level sensor faulty.
- High contact resistance.
- Signal lead short-circuited to ground.

Start fault-tracing at step 1, below.

1) Checking Fuel Level Sensor:





- Ignition off.
- Expose fuel gauge connector. Service and Repair
- Undo fuel level sensor connector C/BB.
- Connect an ohmmeter between terminals 1 and 2 on fuel level sensor connector C/BB.
- Ohmmeter should read 8 - 330 Ohms.

If reading is correct, check ground lead. See step 2, below.
If reading is incorrect, fault is in fuel level sensor. Replace fuel level sensor and test.

2) Checking Ground Lead:





- Ignition off.
- Connect an ohmmeter between terminal 2 on cable harness connector C/BB and ground.
- Ohmmeter should read approx. 0 ohm.

If reading is correct, check test signal to fuel level sensor. See step 4, below.
If reading is incorrect, check ground from instrument panel. See step 3, below.

3) Checking Ground from Instrument Panel:





- Ignition off.
- Expose instrument panel. (Remove Dash Board Cover) Service and Repair
- Undo instrument panel connector.





- Connect test box to cable harness connector and check ground points. Connecting Test Box
- Connect test box between instrument panel and cable harness connector.





- Connect an ohmmeter across # 4 (# A4) and # 15 (# A15) on test box.
- Ohmmeter should read approx. 0 Ohm.

If reading is correct there is an open-circuit in ground lead between terminal 2 in cable harness connector C/BB and instrument panel terminal # A4.
- Check ground lead and connections for open-circuit. Permanent Fault
If reading is incorrect, fault is in instrument panel printed circuit board.
- Replace printed circuit board. Service and Repair (Individual Component Replacement)

4) Checking Test Signal to Fuel Level Sensor:





- Ignition on.
- Connect a voltmeter across terminals 1 and 2 on cable harness connector C/BB.
- Voltmeter should read approx. 4.8 V.

If reading is correct: Contact resistance in signal lead between instrument panel terminal # A5 and terminal 1 on cable harness connector C/BB.
- Check signal lead and connections for contact resistance. Checking Cables and Terminals

If voltmeter reading equals battery voltage: Short-circuit to battery voltage in signal lead between terminal 1 on fuel level sensor connector C/BB and instrument panel terminal # A5.
- Check signal lead and connections for short-circuit to battery supply. Checking Cables and Terminals

If voltmeter reads 0 V, check test signal from instrument panel. See step 5, below.

5) Checking Test Signal from Instrument Panel:





- Ignition off.
- Expose instrument panel. (Remove Dash Board Cover.) Service and Repair
- Undo instrument panel connector.





- Connect test box to cable harness connector and check ground points. Connecting Test Box
- Connect test box between instrument panel and cable harness connectors.
- ignition on.





- Connect a voltmeter between # 5 (# A5) and # 4 (# A4) on test box.
- Voltmeter should read approx. 4.8 V.

If reading is OK there is an open-circuit in signal lead between instrument panel terminal # A5 and terminal 1 in cable harness connector C/BB.
- Check signal lead and connections for open-circuit. Checking Cables and Terminals

If reading is incorrect the fault is in the fuel gauge.
- Replace fuel gauge and test. Service and Repair (Individual Component Replacement.)