• | 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 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 ignition is ON. |
• | The system voltage is between 11-16 volts. |
• | The fuel level signal voltage is greater than 98 percent (less than 0.4 volt). |
• | The above condition is present for greater than 10 seconds. |
• | The fuel gage defaults to empty. |
• | The check gages indicator illuminates. |
• | The ECM records the operating conditions at the time the diagnostic fails. The ECM displays 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
Ignition ON, observe the scan tool Fuel Level Sensor parameter. The reading should be between 0.9-2.5 volts.
⇒ | If less than the specified value, test the signal circuit terminal B for a short to ground. If the circuit tests normal, replace the ECM. |
⇒ | If not within the specified range, replace the fuel level sensor. |
Perform the Diagnostic Repair Verification after completing the diagnostic procedure
• | Control Module References for the ECM replacement, setup, and programming |