DTC P0463
Circuit Description
The fuel level sender changes resistance based on fuel level. The PCM monitors the signal circuit of the fuel level sender in order to determine fuel level. When the fuel tank is full, the sender resistance is high and the PCM senses a high signal voltage. When the fuel tank is empty, the sender resistance is low and the PCM senses a low signal voltage. The PCM uses the signal circuit of the fuel level sender in order to calculate the total remaining fuel (%) in the tank. The PCM sends the fuel level percent via the class 2 serial data circuit to the instrument cluster in order to control the fuel gauge. The fuel level information is also used for misfire and EVAP diagnostics.
Conditions for Running the DTC
The ignition is ON.
Conditions for Setting the DTC
• The fuel level signal is greater than 98%.
• The above condition is present for greater than 20 seconds.
Action Taken When the DTC Sets
• The fuel gauge defaults to empty.
• The low fuel indicator illuminates.
• The PCM records the operating conditions at the time the diagnostic fails. The 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 PCM receives the clear code command from the scan tool.
Diagnostic Aids
Use the Freeze Frame and/or Failure Records data in order to locate an intermittent condition. If you cannot duplicate the DTC, the information included in the Freeze Frame and/or Failure Records data may aid in determining the number of miles since the DTC set. The Fail Counter and Pass Counter can also aid in determining the number of ignition cycles that the diagnostic reported a pass and/or fail. Operate the vehicle within the same freeze frame conditions (RPM, load, vehicle speed, temperature, etc.). This will isolate when the DTC failed.
Refer to
Testing for Intermittent Conditions and Poor Connections in Wiring Systems.
Test Description
The number below refers to the step number on the diagnostic table.
- Tests for the proper operation of the circuit in the low voltage range.
Step
Action
Value(s)
Yes
No
Schematic Reference: Instrument Cluster Schematics
1
Did you perform the Instrument Cluster Diagnostic System Check?
--
Go to
Step 2
Go to
Diagnostic System Check - Instrument Cluster
2
- Install the scan tool.
- Turn ON the ignition, with the engine OFF.
- With the scan tool, observe one of the following fuel level parameters:
• Fuel Tank Level Remaining % parameter in the PCM Enhanced Evap Data list -gas only
• Fuel Level Sensor % parameter in the Engine Data Fuel System display-6.6L diesel only
Does the scan tool indicate that the Fuel Tank Level Remaining % or the Fuel Level Sensor % parameter is greater than the specified value?
98%
Go to
Step 3
Go to Diagnostic Aids
3
- Turn OFF the ignition.
- Disconnect C152.
- Connect a 3 amp fused jumper wire between the signal circuit of the fuel level sender and the low reference circuit of the fuel level sender (male terminal side).
- Turn ON the ignition, with the engine OFF.
- With the scan tool, observe the fuel level parameter.
Does the scan tool indicate that the Fuel Tank Level Remaining % or the Fuel Level Sensor % parameter is less than the specified value?
4%
Go to
Step 6
Go to
Step 4
4
Test the signal circuit of the fuel level sender for an open, a high resistance, or a short to voltage. Refer to
Circuit Testing and
Wiring Repairs in Wiring Systems.
Did you find and correct the condition?
--
Go to
Step 12
Go to
Step 5
5
Test the low reference circuit of the fuel level sender for an open, a high resistance, or a short to voltage. Refer to
Circuit Testing and
Wiring Repairs in Wiring Systems.
Did you find and correct the condition?
--
Go to
Step 12
Go to
Step 9
6
Test the signal circuit of the fuel level sender for an open, a high resistance, or a short to voltage between C152 and the fuel level sender. Refer to
Circuit Testing and
Wiring Repairs in Wiring Systems.
Did you find and correct the condition?
--
Go to
Step 12
Go to
Step 7
7
Test the low reference circuit of the fuel level sender for an open, a high resistance, or a short to voltage between C152 and the fuel level sender. Refer to
Circuit Testing and
Wiring Repairs in Wiring Systems.
Did you find and correct the condition?
--
Go to
Step 12
Go to
Step 8
8
Inspect for poor connections at the harness connector of the fuel level sender. Refer to
Testing for Intermittent Conditions and Poor Connections and
Connector Repairsin Wiring Systems.
Did you find and correct the condition?
--
Go to
Step 12
Go to
Step 10
9
Inspect for poor connections at the harness connector of the PCM. Refer to
Testing for Intermittent Conditions and Poor Connections and
Connector Repairs in Wiring Systems.
Did you find and correct the condition?
--
Go to
Step 12
Go to
Step 11
10
Replace the fuel level sender. Refer to the following procedures:
Did you complete the replacement?
--
Go to
Step 12
--
11
Important: Program the replacement PCM.
Replace the PCM. Refer to the following procedures:
Did you complete the replacement?
--
Go to
Step 12
--
12
- Use the scan tool in order to clear the DTCs.
- Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text.
Does the DTC reset?
--
Go to
Step 2
System OK
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