DTC P0462: Fuel Level Sensor Circuit Low Input
- Check speedometer and tachometer operation. If speedometer and tachometer operate normally, go to next step. If speedometer and tachometer do not operate normally, repair or replace instrument cluster.
- Turn ignition on. Using a voltmeter connected to ground, backprobe ECM connector B136 (30-pin connector) terminal No. 27. See Figure. If voltage is less than .12 volt, go to next step. If voltage is .12 volt or more, monitor voltage while wiggling harness and ECM connector. If voltage changes less than .12 volt, repair poor contact at ECM. If voltage change is not less than .12 volt, circuit has returned to normal. Check for poor contact at fuel pump, instrument cluster, in-line and ECM connectors.
- Turn ignition off. Remove service hole cover located in left rear of trunk floor (sedan), or luggage compartment floor (wagon). Disconnect in-line connector located between rear wiring harness and fuel tank harness (nearest fuel tank). Turn ignition on. Using voltmeter connected to ground, backprobe ECM connector B136 (30-pin connector) terminal No. 27. If voltage less than .12 volt, go to next step. If voltage is .12 volt or more, go to step 6.
- Turn ignition off. Disconnect instrument panel electrical harness connector (13-pin on Forester, 10-pin on Impreza, 30-pin on Legacy). See Fig 1, Fig 2 and Fig 3
. Using an ohmmeter connected to ground, backprobe ECM connector B136 (30-pin connector) terminal No. 27. If resistance is more than one megohm, go to next step. If resistance is less than one megohm, repair short in harness between ECM connector B136 (30-pin connector) and instrument cluster connector. See appropriate wiring diagram in WIRING DIAGRAMS
article.
Courtesy of SUBARU OF AMERICA, INC.
Courtesy of SUBARU OF AMERICA, INC.
Courtesy of SUBARU OF AMERICA, INC.
- Leave instrument cluster connector disconnected. Use an ohmmeter to measure resistance between ECM connector B136 (30-pin connector) terminal No. 27 and instrument cluster connector terminal No. 4 on Forester, No. 8 on Impreza or No. 3 on Legacy. If resistance is more than 10 ohms, repair open between ECM connector B136 (30-pin connector) and instrument cluster connector. If resistance is 10 ohms or less, repair or replace instrument cluster.
- Turn ignition off. Disconnect fuel sub level sensor 2-pin connector. Measure resistance between ground and sensor connector terminal No. 1. See Figure. If resistance is more than one megohm, leave connector disconnected and go to next step. If resistance is less than one megohm, repair short to ground in fuel tank harness.
- Disconnect electrical connector at fuel pump. With fuel sub level sensor 2-pin connector still disconnected, use ohmmeter to measure resistance between ground and connector terminal No. 2. If resistance is less than one megohm, repair short to ground in fuel tank harness. If resistance is more than one megohm or more, go to next step.
- Remove fuel pump assembly from fuel tank. With float set to full position, measure resistance between terminals No. 3 and 6 of 6-pin fuel tank connector. See Figure. If resistance is between .5 and 2.5 ohms, go to next step. If resistance is not between .5 and 2.5 ohms, replace fuel level sensor.
- Remove fuel sub level sensor. With float set to full position, measure resistance between terminals of fuel sub level sensor. See Figure. If resistance is between .5 and 2.5 ohms, repair poor contact between ECM and instrument cluster. If resistance is not between .5 and 2.5 ohms, replace fuel sub level sensor.