2010 Cadillac CTS Sedan AWD V6-3.6L Page 1435
6. If all circuits test normal, test or replace the EVAP purge solenoid.
Repair Instructions
Perform the Diagnostic Repair Verification (See: Verification Tests) after completing the diagnostic procedure.
* Evaporative Emission Canister Purge Solenoid Valve Replacement (LF1) (See: Powertrain Management/Emission Control
Systems/Evaporative Emissions System/Canister Purge Solenoid/Service and Repair)Evaporative Emission Canister Purge Solenoid Valve
Replacement (LLT) (See: Powertrain Management/Emission Control Systems/Evaporative Emissions System/Canister Purge
Solenoid/Service and Repair)
* Control Module References (See: Testing and Inspection/Programming and Relearning) for ECM replacement, setup, and programming
P0461
DTC P0461
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic System
Check - Vehicle) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Strategy Based Diagnosis) for an
overview of the diagnostic approach.
* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure
Instructions) provides an overview of each diagnostic category.
DTC Descriptor
DTC P0461
- Fuel Level Sensor 1 Performance
Diagnostic Fault Information
Circuit/System Description
The primary fuel level sender and the secondary fuel level sender changes resistance based on fuel level. The engine control module (ECM)
monitors the signal circuits of the primary fuel level sender and the secondary fuel level sender in order to determine the fuel level. When the fuel
tank is full, the resistances of both fuel level senders are low and the ECM senses a low signal voltage on both the signal circuits of the primary fuel
level sender and the secondary fuel level sender. When the fuel tanks are empty, the resistances of the fuel level senders are high and the ECM
senses a high signal voltage. The ECM uses the signal circuits of the primary fuel level sender and the secondary fuel level sender in order to
calculate the percentage of remaining fuel in the tank. The ECM sends the fuel level percentage via serial data circuit to the instrument cluster in
order to control the fuel gauge.
Conditions for Running the DTC
* The engine is running.
* No fuel level sensor signal failure present.
* The fuel level state is stable.
Conditions for Setting the DTC
* The ECM detects a difference between the engine consumed fuel and change of the fuel level signal of less than 1 L (0.26 gallon) over a
range of 30 L (7.92 gallons) or 45.6 percent of the primary fuel tank.
* The above condition is present for about 300 seconds.
Action Taken When the DTC Sets
* The fuel gauge defaults to empty.
* The low fuel indicator illuminates.
* The ECM records the operating conditions at the time that the diagnostic test fails. The ECM displays the failure information in the Failure
