Diagnostic Instructions
DTC Descriptor
DTC P0463: Fuel Level Sensor Circuit High Voltage
Diagnostic Fault Information
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
P0464
| P0463
| P0461
|
Fuel Level Sensor Low Reference Circuit
| --
| P0463
P0464
| P0463
| P0461
|
Circuit/System Description
The fuel level sensor changes resistance in response to the fuel level. The engine control module (ECM)/ powertrain control module (PCM) monitors the signal circuit of the fuel level sensor in order to determine the fuel level. When the fuel tank is full,
the fuel level sensor resistance is low and the ECM/PCM senses a low signal voltage. When the fuel tank is empty, the fuel level sensor resistance is high and the ECM/PCM senses a high signal voltage. The ECM/PCM uses the signal circuit of the fuel level sensor
in order to calculate the percentage of fuel remaining in the tank. The ECM/PCM sends the fuel level information via the serial data circuit to the body control module (BCM). The BCM sends the fuel information to the instrument panel cluster via the serial data
circuit in order to control the fuel gage and display the fuel level.
Conditions for Running the DTC
| • | The ignition is ON, with the engine running. |
| • | The system voltage is between 9-16 volts. |
Conditions for Setting the DTC
| • | The sensor output is greater than 2.9 volts. |
| • | The above condition is present for greater than 30 seconds. |
Action Taken When the DTC Sets
| • | The fuel gage defaults to empty. |
| • | The low fuel indicator illuminates. |
| • | The ECM/PCM records the operating conditions at the time that the diagnostic test fails. The ECM/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 ECM/PCM receives a clear code command from the scan tool. |
Reference Information
Schematic Reference
Connector End View Reference
Electrical Information Reference
Scan Tool Reference
Scan Tool Data List
Circuit/System Verification
Ignition ON, observe the scan tool Fuel Tank Level Remaining parameter. The reading should be between 4 percent and 98 percent.
Circuit/System Testing
- Ignition OFF, disconnect the harness connector at the fuel level sensor.
- Ignition OFF, test for less than 1 ohm of resistance between the fuel level sensor low reference circuit terminal D and ground.
| ⇒ | If greater than the specified range, test the low reference circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the ECM/PCM. |
- Install a 3A fused jumper wire between the fuel level sensor signal circuit terminal C and the low reference circuit terminal D. Verify the Fuel Tank Level Remaining parameter is greater than 98 percent.
| ⇒ | If less than the specified range, test the fuel level sensor signal circuit for a short to voltage or an open/high resistance. If the circuit test normal, replace the ECM/PCM. |
- If all circuit test normal, perform the fuel level sensor component test before replacing the fuel level sensor.
Component Testing
- Ignition OFF, disconnect the harness connector at the fuel level sensor.
- While sweeping the fuel level sensor through its full range of motion, test for a minimum value less than 41 ohms and a maximum value greater than 119 ohms of resistance between signal terminal C and the low reference terminal D.
| ⇒ | If not within the specified range, replace the fuel level sensor. |
Repair Instructions
Perform the
Diagnostic Repair Verification
after completing the diagnostic procedure.
