For 1990-2009 cars

### Diagnostic Instructions

• | 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.

### 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

• | Instrument Cluster Schematics

• | Engine Controls Schematics for the 2.4L engine

• | Engine Controls Schematics for the 2.2L engine

• | Engine Controls Schematics for the 2.0L engine

#### Connector End View Reference

• | Displays and Gages Connector End Views

• | Engine Control Module Connector End Views for the 2.4L engine

• | Engine Control Module Connector End Views for the 2.2L engine

• | Powertrain Control Module Connector End Views for the 2.0L engine

#### Electrical Information Reference

• | Circuit Testing

• | Connector Repairs

• | Testing for Intermittent Conditions and Poor Connections

• | Wiring Repairs

#### 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

1. Ignition OFF, disconnect the harness connector at the fuel level sensor.
2. 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.

3. 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.

4. If all circuit test normal, perform the fuel level sensor component test before replacing the fuel level sensor.

### Component Testing

1. Ignition OFF, disconnect the harness connector at the fuel level sensor.
2. 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.

• | Fuel Level Sensor Replacement for the 2.4L engine

• | Fuel Level Sensor Replacement for the 2.2L engine

• | Fuel Level Sensor Replacement for the 2.0L engine

• | Control Module References for the ECM replacement, setup and programming