Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means that the car's computer is getting a signal from a part called the EGR sensor that is too low. It's like when you try to listen to music, but the volume is turned down too low to hear anything.
The EGR (Exhaust Gas Recirculation) sensor measures the amount of exhaust gases being recirculated back into the engine. A low circuit signal indicates that the sensor is not sending enough voltage back to the engine control module.
The P0405 code is triggered when the engine control module (ECM) detects a voltage signal from the EGR position sensor that is below the expected range. This could be due to a malfunctioning sensor, wiring issues, or a faulty ECM.
• Check Engine Light is on
• Poor engine performance
• Increased emissions
• Faulty EGR position sensor
• Wiring issues or poor connection in the EGR sensor circuit
• Faulty engine control module (ECM)
EGR: Exhaust Gas Recirculation
ECM: Engine Control Module
• Use an OBD-II scanner to confirm the code.
• Inspect the EGR sensor and its wiring for damage or disconnection.
• Test the EGR sensor voltage with a multimeter.
• Replace the EGR position sensor.
• Repair or replace damaged wiring or connectors.
• Reprogram or replace the ECM if necessary.
• OBD-II scanner
• Multimeter
• Socket set
$150 - $400
Moderate
• Ford F-150
• Chevrolet Silverado
• Toyota Camry
• Regularly inspect EGR system components.
• Ensure proper maintenance of vehicle's electrical system.
• Use quality fuel to reduce carbon buildup.
Sensor Issue
• Do not ignore the Check Engine Light.
• Have the vehicle inspected by a professional if unsure.
• Avoid driving the vehicle excessively until repaired.
Check if the vehicle's warranty covers emissions-related components.
The P0405 code has been a common issue in vehicles with EGR systems since the introduction of OBD-II in the mid-1990s.
Moderate – It's important to address this issue to prevent increased emissions and potential engine performance problems.
Driving with a malfunctioning EGR system can lead to increased emissions, which may be illegal in some areas.
• Engine at operating temperature
• Vehicle at idle
The EGR sensor is typically located near the EGR valve on the engine.
Q: Can I drive with a P0405 code?
A: It's not recommended to drive for long periods with this code, as it can lead to increased emissions and potential engine performance issues.
Q: How do I reset the Check Engine Light after fixing the issue?
A: You can reset the light using an OBD-II scanner or by disconnecting the battery for a few minutes, though the latter may reset other settings in the vehicle.
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