P0443
DTC P0443
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis Strategy Based Diagnosis for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions Diagnostic Procedure Instructions provides an overview of each diagnostic category.
DTC Descriptors
DTC P0443
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Evaporative Emission (EVAP) Purge Solenoid Valve Control Circuit
Diagnostic Fault Information
Circuit/System Description
An ignition voltage is supplied directly to the evaporative emission (EVAP) canister purge solenoid valve. The engine control module (ECM) grounds the evaporative emission canister purge solenoid valve control circuit through an internal switch called a driver. The ECM monitors the status of the driver. The evaporative emission canister purge solenoid valve is pulse width modulated (PWM). A scan tool will display the amount of ON time as a percentage.
Conditions for Running the DTC
* The ignition is ON.
* The system voltage is between 9-32 V.
* The DTC runs continuously when the above conditions are met.
Conditions for Setting the DTC
The ECM detects that the commanded state of the driver and the actual state of the control circuit do not match for a minimum of 5 s.
Action Taken When the DTC Sets
DTC P0443 is a Type B DTC.
Conditions for Clearing the DTC
DTC P0443 is a Type B DTC.
Reference Information
Schematic Reference
Engine Controls Schematics [1][2]Electrical Diagrams
Description and Operation
Evaporative Emission Control System Description Description and Operation
Connector End View Reference
Component Connector End Views Fuel Pump and Level Sensor Assembly
Electrical Information Reference
* Circuit Testing Circuit Testing
* Troubleshooting with a Test Lamp Troubleshooting with a Test Lamp
* Testing for Intermittent Conditions and Poor Connections Testing for Intermittent Conditions and Poor Connections
* Wiring Repairs Wiring Repairs
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Scan Tool Reference
Control Module References Control Module References for scan tool information
Circuit/System Verification
1. Ignition ON, engine OFF, you should hear a clicking sound when the evaporative emission canister purge solenoid valve is commanded to 50% with a scan tool. The clicking sound should stop when the evaporative emission canister purge solenoid valve is commanded to 0%. The rate at which the valve cycles should increase when the commanded state is increased, and decrease when the commanded state is decreased.
2. Operate the vehicle within the Conditions for Running the DTC to verify the DTC does not reset. or operate the vehicle within the conditions from the Freeze Frame/Failure Records data.
Circuit/System Testing
1. Ignition OFF, disconnect the harness connector at the Q12 Evaporative Emission Purge Solenoid Valve.
2. Ignition ON, verify a test lamp illuminates between the Q12 Evaporative Emission Purge Solenoid Valve voltage supply circuit terminal 2 and ground.
• If the test lamp does not illuminate, test the voltage supply circuit for a short to ground or an open/high resistance. If the circuit tests normal and the voltage supply circuit fuse is open, test or replace the Q12 Evaporative Emission Purge Solenoid Valve.
3. Connect a test lamp between the voltage supply circuit terminal 2 and the control circuit terminal 1 at the Q12 Evaporative Emission Purge Solenoid Valve.
4. Command the EVAP canister purge solenoid valve to 50% with a scan tool. The test lamp should respond to the command.
• If the test lamp is always ON, test the control circuit for a short to ground. If the circuit tests normal, replace the K20 Engine Control Module.
• If the test lamp is always OFF, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the K20 Engine Control Module.
5. If all circuits test normal, replace the Q12 Evaporative Emission Purge Solenoid Valve.
Repair Instructions
Perform the Diagnostic Repair Verification Verification Tests after completing the diagnostic procedure.
* Evaporative Emission Canister Purge Solenoid Valve Replacement Service and Repair
* Control Module References Control Module References for ECM replacement, programming and setup