
P1490 (Volkswagen, Audi, Skoda, Seat) EVAP Canister Vent Solenoid 2 - Short to Ground
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P1490 - OBD-II Trouble Code Technical Description
Trouble code P1490 indicates a short to ground in the EVAP canister vent solenoid 2 circuit in Volkswagen, Audi, Skoda, Seat vehicles.
What does the fault code mean P1490?
Trouble code P1490 indicates a possible short to ground in the EVAP solenoid valve 2 circuit. This valve controls the flow of fuel vapor in the EVAP system, which is designed to capture and process fuel vapor to prevent its release into the atmosphere. A short to ground may mean that the valve circuit has made an unexpected connection to vehicle ground, which may cause the valve to malfunction or become completely inoperable.

Possible reasons
Several possible reasons for the P1490 trouble code:
- Damage to wiring or connectors: The wiring connecting EVAP canister vent solenoid valve 2 to the vehicle's electrical system may be damaged, broken, or oxidized at the contacts. This may cause a short to ground in the circuit.
- Solenoid valve failure: The valve itself may be damaged or malfunctioning, causing its electrical circuit to malfunction.
- Relay or fuse problems: A malfunctioning relay or fuse that supplies power to the solenoid valve can cause the valve to not operate properly and cause code P1490 to appear.
- Incorrect installation or repair: Improper installation or repair of the electrical circuit or components of the canister vent system can cause problems, including a short to ground in the valve circuit.
- Unauthorized modifications: Unauthorized changes or modifications to the vehicle system, especially in the electrical field, may also cause this error to appear.
To pinpoint the cause of the P1490 trouble code, it is recommended that you conduct a thorough diagnostic test, which includes checking electrical components, wiring, connectors, and using a diagnostic scan tool to analyze system data.
What are the symptoms of a fault code? P1490?
Symptoms for a P1490 trouble code can vary depending on the specific cause of the problem and the vehicle's design, but some possible symptoms that may occur include:
- «Check Engine» indicator: One of the most common symptoms when any error code appears, including P1490, is the “Check Engine” light on the dashboard comes on. This is a warning that there is a problem with the engine management system.
- Unstable idle: Incorrect operation of EVAP canister vent solenoid valve 2 may cause the engine to idle rough. The car may shake or jerk when idling.
- Performance degradation: Incorrect operation of the canister ventilation system may affect engine performance, which may manifest itself in a decrease in power or worse acceleration dynamics.
- Increased fuel consumption: A faulty solenoid valve can result in improper fuel vapor control, which in turn can increase fuel consumption.
- Presence of fuel odor: If the fuel evaporation control system, including EVAP canister vent valve 2, malfunctions, a fuel odor may occur around the vehicle.
- Unsuccessful attempts to pass technical inspection: In areas where vehicles are inspected, a P1490 fault may result in vehicle inspection failures.
If any of the above symptoms occur, it is recommended that you contact a qualified auto mechanic or diagnostic technician to further inspect and resolve the problem.
How to diagnose a fault code P1490?
The following approach is recommended to diagnose DTC P149:
- Reading the error code: Use a diagnostic scanner to read the P1490 fault code from the engine management system. Write down the error code and any additional codes that may be present.
- Checking wiring and connectors: Carefully inspect the wiring and connectors connecting EVAP canister ventilation solenoid valve 2 to the vehicle's electrical system. Check them for damage, breaks, oxidation or loose connections.
- Voltage test: Use a multimeter to check the voltage in the solenoid valve circuit. Make sure the voltage matches the required values specified in the technical documentation for your specific vehicle.
- Resistance test: Measure the resistance of the solenoid valve. Make sure that the resistance is within the acceptable values specified in the technical documentation.
- Checking relays and fuses: Check the condition and functionality of the relays and fuses responsible for powering the EVAP canister ventilation solenoid valve 2. Make sure they are in good working order and provide sufficient power to the valve.
- Checking other EVAP system components: Check other EVAP canister vent system components, such as sensors and valves, for damage or malfunction.
- Additional tests: If necessary, perform additional tests recommended by the vehicle manufacturer to diagnose the problem.
- Using diagnostic data: Use the diagnostic data provided by the diagnostic scanner to analyze system performance and identify any anomalies.
Once the diagnostics are completed, you can pinpoint the cause of the P1490 trouble code and begin making the necessary repairs or replacing the faulty components. If you do not have experience in diagnosing and repairing vehicles, it is recommended that you contact a qualified auto mechanic or auto repair shop.
Diagnostic errors
When diagnosing DTC P1490, the following errors may occur:
- Incorrect interpretation of error code: Some mechanics may focus solely on the error code itself, without considering other possible causes such as damaged wiring or faulty other system components.
- Insufficient checking of wiring and connectors: Wiring and connectors may be hidden inside the vehicle or under the hood. Incorrect or insufficient testing of these components may lead to incorrect conclusions about the cause of the malfunction.
- Incorrect parameter measurement: Incorrect measurement of voltage, resistance or other parameters may result in incorrect diagnosis. Insufficiently accurate or uncalibrated instruments can cause errors in data interpretation.
- Skip checking other EVAP system components: The P1490 code indicates a problem in the EVAP canister vent solenoid valve 2 circuit, but improperly repaired or other faulty system components can also cause this error code to occur. Skipping other components may result in an incomplete or incorrect diagnosis.
- Improper repair: Improperly replacing or repairing components unrelated to the root cause of the error can waste time and resources.
- Ignoring technical documentation: Vehicle manufacturers provide diagnostic and repair guidelines. Ignoring these recommendations may result in incorrect diagnosis and repair.
To avoid these mistakes, it is important to follow a methodical approach to diagnosis and perform all necessary checks and tests.
How serious is the fault code? P1490?
Trouble code P1490 indicates potential problems with the evaporative emissions control (EVAP) system, which can have varying consequences depending on your specific situation. A few aspects to consider when assessing the severity of this DTC:
- Environmental consequences: Problems in the fuel evaporative control system can cause fuel vapor to leak into the atmosphere, contributing to environmental pollution. In some regions this may result in fines or other penalties.
- Engine performance: Incorrect operation of the EVAP system can adversely affect engine performance, including poor efficiency and fuel economy.
- Technical inspection: In some locations, a vehicle with an active error code may not pass inspection, resulting in temporary restrictions on the use of the vehicle and additional costs for repairs.
- Security: Although the P1490 code itself does not usually pose an immediate safety threat, improper fuel evaporation management can affect the performance of the engine and other vehicle systems, which in turn can affect driving safety.
So, although the P1490 code is not an alarm, it does indicate a serious problem that requires careful attention and timely resolution. It is necessary to begin diagnostics and repairs as soon as possible to avoid negative consequences for the environment, vehicle performance and its further operation.
What repair will help eliminate the code? P1490?
Troubleshooting the P1490 trouble code involves diagnosing and repairing evaporative control system (EVAP) components, there are several steps that can help resolve this trouble code:
- Checking and replacing EVAP canister ventilation solenoid valve 2: If diagnostics show that the solenoid valve is faulty, it must be replaced with a new original or high-quality analogue.
- Checking and repairing wiring and connectors: Carry out a thorough check of the wiring and connectors connecting the solenoid valve to the vehicle's electrical system. If necessary, replace damaged wires or connectors.
- Checking relays and fuses: Check the condition of the relays and fuses that supply power to the solenoid valve. Replace them if they are damaged or faulty.
- Diagnostics ECU: If replacing the valve and checking the wiring does not resolve the problem, further diagnostics and, if necessary, repair or replacement of the electronic control unit (ECU) may be required.
- Checking other EVAP system components: Check other evaporative control system components, such as sensors and valves, for damage or malfunction. Repair or replace if problems are found.
- Thorough inspection and testing: After completing the repair, perform a thorough system check using a diagnostic scanner and other necessary tools to ensure that the problem has been completely resolved.
Repairs must be performed by a qualified technician using the correct parts and products to ensure proper operation of the system and prevent the problem from reoccurring.

