P0443
DTC P0443 (LUW)
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 Descriptor
DTC P0443
- Evaporative Emission (EVAP) Purge Solenoid Valve Control Circuit
Diagnostic Fault Information
Circuit/System Description
Ignition voltage is supplied directly to the EVAP canister purge solenoid valve. The engine control module (ECM) grounds the EVAP canister purge solenoid valve control circuit through an internal switch called a driver. The ECM monitors the status of the driver. The EVAP 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 EVAP canister purge solenoid valve is enabled.
* The powertrain relay voltage is between 11-32 V.
* The DTC runs continuously when the above condition is met.
Conditions for Setting the DTC
P0443
The ECM detects that the commanded state of the driver and the actual state of the control circuit do not match for greater than 5 s.
Action Taken When the DTC Sets
DTCs P0443 is a Type B DTC.
Conditions for Clearing the DTC
DTCs P0443 is a Type B DTC.
Reference Information
Schematic Reference
Engine Controls Schematics [1][2]Electrical Diagrams
Connector End View Reference
Component Connector End Views Fuel Pump and Level Sensor Assembly
Description and Operation
Evaporative Emission Control System Description Description and Operation
Electrical Information Reference
* Circuit Testing Circuit Testing
* Connector Repairs Connector Repairs
* 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, verify the scan tool control circuit status parameters listed below do not display Malfunction:
* EVAP Purge Solenoid Valve Control Circuit High Voltage Test Status
* EVAP Purge Solenoid Valve Control Circuit Open Test Status
* EVAP Purge Solenoid Valve Control Circuit Low Voltage Test Status
2. Verify the scan tool control circuit status parameters listed below do not display Malfunction while the solenoid is commanded to 100% with a scan tool:
* EVAP Purge Solenoid Valve Control Circuit High Voltage Test Status
* EVAP Purge Solenoid Valve Control Circuit Open Test Status
* EVAP Purge Solenoid Valve Control Circuit Low Voltage Test Status
3. Operate the vehicle within the Conditions for Running the DTC to verify the DTC does not reset. You may also operate the vehicle within the conditions that you observed 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 that a test lamp illuminates between the 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 all components connected to the ignition voltage circuit and replace as necessary.
3. Ignition OFF, test for less than 0.3 V between the control circuit terminal 1 and ground.
• If more than the specified range, repair the short to B+. If the circuit tests normal, replace the K20 Engine Control Module.
4. Ignition OFF, disconnect the K20 Engine Control Module. Test for less than 5 ohms between the Q12 Evaporative Emission Purge Solenoid Valve connector terminal 1 and the K20 Engine Control Module terminal 66 X2.
• If greater than the specified range, repair the open circuit. If the circuit tests normal, replace the K20 Engine Control Module.
5. If all circuits test normal, test or replace the EVAP purge solenoid.
Component Testing
Static Test
1. Ignition OFF, disconnect the harness connector at the Q12 Evaporative Emission Purge Solenoid Valve.
2. Test for 10-30 ohms between the voltage supply circuit terminal 2 and the control circuit terminal 1.
• If not within the specified range, replace the Q12 Evaporative Emission Purge Solenoid Valve.
Repair Instructions
Perform the Diagnostic Repair Verification Verification Tests after completing the repair.
* Evaporative Emission Canister Purge Solenoid Valve Replacement Service and Repair
* Control Module References Control Module References for ECM replacement, programming, and setup.