DTC Troubleshooting

Control System DTCs

DTC Troubleshooting: P0462

DTC P0462 : Fuel Level Sensor (Fuel Gauge Sending Unit) Circuit Low Voltage

NOTE: Before you troubleshoot, record all freeze data and any on-board snapshot, and review the general troubleshooting information How To Troubleshoot The Fuel And Emissions Systems.

1. Problem verification:

Problem verification
-1. Turn the ignition switch to ON (II).

-2. Clear the DTC with the HDS.

-3. Wait 5 seconds.

-4. Check for Pending or Confirmed DTCs with the HDS.

Is DTC P0462 indicated?
-YES- The failure is duplicated. Go to step 2.
-NO- Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the gauge control module (tach) and the fuel gauge sending unit.

2. Fuel gauge sending unit check:

Fuel gauge sending unit check
-1. Turn the ignition switch to LOCK (0).

-2. Remove the access panel from the floor.

-3. Disconnect the following connector.





-4. Turn the ignition switch to ON (II).

-5. Wait 5 seconds.

-6. Check for Pending or Confirmed DTCs with the HDS.

Is DTC P0463 indicated?
-YES- Replace the fuel gauge sending unit Fuel Pump/Fuel Gauge Sending Unit Removal and Installation, then do the repair verification.
-NO- The fuel gauge sending unit is OK. Go to step 3.

3. Determine possible failure area (FUEL_GAGE+ line, others):

Determine possible failure area (FUEL_GAGE+ line, others)
-1. Measure the voltage between test points 1 and 2.









Is there battery voltage?
-YES- Go to step 5.
-NO- Go to step 4.

4. Shorted wire check (FUEL_GAGE+ line):

Shorted wire check (FUEL_GAGE+ line)
-1. Turn the ignition switch to LOCK (0).

-2. Remove the gauge control module (tach). Gauge Control Module (Tach) Removal and Installation

-3. Disconnect the following connector.





-4. Check for continuity between test points 1 and 2.









Is there continuity?
-YES- Repair a short in the FUEL_GAGE+ wire between the gauge control module (tach) and the fuel tank unit, then do the repair verification.
-NO- The FUEL_GAGE+ wire is OK. Replace the gauge control module (tach) Gauge Control Module (Tach) Removal and Installation, then do the repair verification.

5. Gauge control module (tach) check:

Gauge control module (tach) check
-1. Reconnect the following connector.





-2. Remove the fuel tank unit. Fuel Tank Unit Removal/Installation

-3. Connect the following connector.





-4. Turn the ignition switch to ON (II).

-5. Clear the DTC with the HDS.

-6. Set the float (A) to the E position.





-7. Check the fuel gauge.

Does the gauge move to the empty position?
-YES- The gauge control module (tach) is OK. Update the ECM ECM/PCM Update if it does not have the latest software, or substitute a known-good ECM Service and Repair, then do the repair verification.
-NO- Replace the gauge control module (tach) Gauge Control Module (Tach) Removal and Installation, then do the repair verification.

Repair verification:

-1. Turn the ignition switch to LOCK (0).

-2. Reinstall all removed parts in the reverse order of removal.

-3. Turn the ignition switch to ON (II).

-4. Reset the ECM with the HDS How To Troubleshoot The Fuel And Emissions Systems.

-5. Do the ECM idle learn procedure ECM/PCM Idle Learn Procedure.

-6. Check for Pending or Confirmed DTCs with the HDS.

Is DTC P0462 indicated?
-YES- Check for poor connections or loose terminals at the gauge control module (tach) and the fuel gauge sending unit. If the ECM was updated, substitute a known-good ECM Service and Repair, then recheck. If the ECM was substituted, go to step 1.
-NO- Troubleshooting is complete. If the ECM was substituted, replace the original ECM Service and Repair. If any other Pending or Confirmed DTCs are indicated, go to the indicated DTC's troubleshooting.