• | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. |
• | Review Strategy Based Diagnosis for an overview of the diagnostic approach. |
• | Diagnostic Procedure Instructions provides an overview of each diagnostic category. |
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
---|---|---|---|---|
Fuel Level Sensor Reference Voltage Circuit | P0462 | -- | -- | P0461 |
Fuel Level Sensor Signal Circuit | P0462 | P0463 1 P0464 | P0463 | P0461 |
Fuel Level Sensor Low Reference Circuit | -- | P0463 1 P0464 | P0463 | P0461 |
1. Fuel Gage Inaccurate or Inoperative |
The fuel level sensor changes resistance based on fuel level. The engine control module (ECM) monitors the signal circuit of the fuel level sensor in order to determine fuel level. When the fuel tank is full, the sensor resistance is low and the ECM senses a low signal voltage. When the fuel tank is empty, the sensor resistance is high and the ECM senses a high signal voltage. The ECM uses the signal circuit of the fuel level sensor in order to calculate the total remaining fuel (percent) in the tank. The ECM sends the fuel level percent via the serial data circuit to the instrument panel cluster (IPC) in order to control the fuel gage. The fuel level information is also used for misfire and evaporative emission (EVAP) diagnostics.
• | The ignition is ON. |
• | The ECM has confirmed that the fuel tank is between 15-85 percent full. |
The ECM does not detect a change in fuel level of at least 3.0L (0.79 gal) over a distance of 320 km (200 mi).
• | The fuel gage defaults to empty. |
• | The low fuel indicator illuminates. |
• | The ECM records the operating conditions at the time the diagnostic fails. The ECM stores the failure information in the Failure Records on the scan tool. |
• | 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 ECM receives the clear code command from the scan tool. |
⇒ | If interference is present, remove the obstruction. |
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
• | Control Module References for the ECM replacement, setup, and programming |