• | 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 | High Resistance | Open | Short to Voltage | Signal Performance |
---|---|---|---|---|---|
Fuel Level Sensor Signal | P0462 | 1 | P0463, P0464 | P0463 | P0461 |
Fuel Level Sensor Low Reference | -- | 1 | P0463, P0464 | P0463 | P0461 |
1. Fuel Gage Inaccurate or Inoperative |
The engine control module (ECM) monitors the signal circuit of the fuel level sender in order to determine fuel level. The fuel level sender consists of a variable resistor that changes resistance based on the fuel level in the tank. The ECM monitors the voltage across the sender resistance in order to determine the fuel level. When the fuel tank is full, the resistance of the fuel level sender is low and the ECM senses a low signal voltage on the signal circuit. When the fuel tank is empty, the resistance of the fuel level sender is high and the ECM senses a high signal voltage. The ECM uses the signal circuit of the fuel level sender in order to calculate the total remaining fuel, in percent. The ECM sends the fuel level percent via the serial data circuit to the instrument cluster in order to control the fuel gage.
• | 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. |
Instrument Cluster Description and Operation
Control Module References for scan tool information
⇒ | If any interference is present, repair the fuel sender interference. |
⇒ | If not within the specified range, replace the fuel level sensor. |
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
• | Fuel Level Sensor Replacement for the 4.2L engine |
• | Fuel Level Sensor Replacement for the 4.8L, 5.3L, 6.0L, 6.2L or 7.0L engines |
• | Control Module References for the ECM replacement, setup, and programming |