P0462

DTC P0462

Diagnostic Instructions

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

DTC Descriptor

DTC P0462
- Fuel Level Sensor 1 Circuit Low Voltage

Diagnostic Fault Information






Circuit/System Description

The fuel level sender changes resistance based on the fuel level. The powertrain control module (PCM) monitors the signal circuit of the fuel level sender in order to determine fuel level. When the fuel tank is full, the sender resistance is low and the PCM senses a low signal voltage. When the fuel tank is empty, the sender resistance is high and the PCM senses a high signal voltage. The PCM uses the signal circuit of the fuel level sender in order to calculate the total remaining fuel percent in the tank. The PCM sends the fuel level message via the CAN serial data circuit to the body control module (BCM). The BCM sends the fuel level percent to the instrument panel cluster (IPC) via the class 2 data circuit to display on the fuel gage. The fuel level information is also used for misfire and evaporative emission (EVAP) diagnostics.

This diagnostic tests for a lower than normal fuel level sender signal.

Conditions for Running the DTC

The ignition is ON, with the engine ON.

Conditions for Setting the DTC

* The fuel level signal is greater than 98 percent.
* The above condition is present for greater than 20 seconds.

Action Taken When the DTC Sets

* The fuel gage defaults to empty.
* The PCM records the operating conditions at the time the diagnostic fails. The PCM displays the failure information in the Failure Records on the scan tool.

Conditions for Clearing the DTC

* The DTC becomes history when the conditions for setting the DTC are no longer present.
* The history DTC clears after 40 malfunction-free warm-up cycles.
* The PCM receives the clear code command from the scan tool.

Diagnostic Aids

Using the Failure Records data may help locate an intermittent condition. If you cannot duplicate the DTC, the information in the Failure Records can help determine how many miles since the DTC set. The Fail Counter and Pass Counter can help determine how many ignition cycles that the diagnostic test reported a pass and/or a fail.

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the fuel level sensors.
2. Ignition ON, verify that the scan tool fuel tank level remaining parameter is less than 4 percent

• If greater than 4 percent, test the signal circuit for a short to ground. If the circuit tests normal, replace the PCM.

3. If all circuits test normal, test or replace the fuel level sensors.

Component Testing

Measure the resistance of the float arm of the fuel level sender while moving the float arm between 40-250 ohms.

If the resistance does not move smoothly across the specified range, replace the fuel level sensor.

Repair Instructions

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

* Primary Fuel Tank Module Replacement
* Secondary Fuel Tank Module Replacement
* Refer to Programming and Relearning for PCM setup and programming. Programming and Relearning