Fuel Gauge Inaccurate or Inoperative

Fuel Gauge Inaccurate or Inoperative

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (Diagnostic System Check - Vehicle) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Strategy Based Diagnosis) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Diagnostic Procedure Instructions)provides an overview of each diagnostic category.

Circuit/System Description

The instrument cluster displays the fuel level based on the information from the engine control module (ECM). The ECM converts the data from the fuel level sensors to a fuel level signal. The ECM sends the fuel level signal via a High Speed CAN-Bus signal to the body control module (BCM). The BCM then sends the information via a Low Speed CAN-Bus signal to the instrument cluster to display the fuel level. When the fuel level falls below 11% the instrument cluster illuminates the low fuel level indicator.

Reference Information
Schematic Reference

Instrument Cluster Schematics (Instrument Cluster Schematics)
Connector End View Reference

Component Connector End Views (Connector End Views By Name)
Description and Operation

Instrument Cluster Description and Operation (Instrument Cluster)
Electrical Information Reference

* Circuit Testing (Circuit Testing)
* Connector Repairs (Connector Repairs)
* Testing for Intermittent Conditions and Poor Connections (Testing for Intermittent Conditions and Poor Connections)
* Wiring Repairs (Wiring Repairs)

Scan Tool Reference

Control Module References (Programming and Relearning)for scan tool information

Circuit/System Verification

1. Ignition ON, perform the Instrument Cluster Gauge Sweep test with the scan tool, verify that the fuel level gauge sweeps from its low to high position.

• If the fuel level gauge does not sweep, replace the P16 instrument cluster.

2. Command the All Indicators test ON and OFF with the scan tool, verify that the low fuel level indicator turns ON and OFF.

• If the low fuel level indicator does not turn ON or OFF as commanded, replace the P16 instrument cluster.

3. Observe the scan tool ECM Fuel Level Sensor parameter. The reading should be 0.5-3.5 V and vary with fuel level.

• If the reading does not vary with fuel level, refer to DTC P0461-P0464 (P0461).

4. If the fuel level gauge does sweep and the low fuel level indicator turns ON and OFF, replace the K20 ECM.

Repair Instructions

Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.

Control Module References (Programming and Relearning)for instrument cluster or ECM replacement, programming and setup