P0443 Code Meaning
The P0443 code signifies a problem with the EVAP system purge valve or its control circuit, as perceived by the Powertrain Control Module (PCM). This code is part of a series that includes P0444 (EVAP Purge Control Valve Circuit Open) and P0445 (EVAP Purge Control Valve Circuit Shorted).
Other Relevant Codes
Other diagnostic trouble codes associated with the EVAP system include P0440-P0449, P0452-P0453, and P0455-P0456.
Symptoms of P0443 Code
While an illuminated check engine light is the most common symptom, additional issues like rough running and hesitation may occur if the purge valve is stuck open. The presence of other stored codes can lead to different symptoms.
Causes of P0443 Code
The P0443 code can be triggered by various issues, including a malfunctioning purge valve, problems with the purge valve circuit (such as loose connections or damaged wires), or in rare cases, a problem with the PCM.
P0443 on Ford Vehicles
On certain Ford vehicles, like the 2011 Ford F-150 XL 3.7L V6, the P0443 code may appear due to specific conditions, including issues with the VPWR circuit, EVAPCP circuit, damaged EVAP purge valve, or PCM.
Ford Diagnostic Steps
For Ford vehicles, the diagnostic process involves monitoring the EVAP purge valve signal PID EVMV or EVAPCP and the signal voltage. The normal functioning range of the valve is outlined, aiding in verification.
Understanding the EVAP System
The Evaporative Control (EVAP) system plays a crucial role in preventing fuel vapors from being released into the atmosphere. The system includes components such as the charcoal canister, which traps fuel vapors when the engine is off.
Diagnosis of P0443 Code
Diagnosing the P0443 code typically involves investigating circuit faults or problems with the purge valve. Professional assistance is recommended for those unsure of their automotive troubleshooting skills.
OBD-II Code Reader
The use of an OBD-II code reader is essential for diagnosis. The process and required steps may vary based on the vehicle manufacturer.
Nissan Altima 2007-2012 Service Manual: P0443 Evap Canister Purge Volume Control Solenoid Valve
For Nissan Altima 2007-2012, the service manual addresses the P0443 code, focusing on the EVAP canister purge volume control solenoid valve.
Description and DTC Logic
The article explains the operation of the EVAP canister purge volume control solenoid valve and provides insight into the DTC logic used for detection.
Confirmation Procedure and Diagnosis
The service manual outlines the steps for confirming the DTC, including specific testing conditions and procedures. It further guides technicians through a comprehensive diagnosis procedure, checking various components and circuits.
A detailed component inspection section is included, covering the EVAP canister purge volume control solenoid valve and related components. This section assists in identifying and addressing potential malfunctions.