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 computer in your car thinks the sensor that checks the temperature of a part called the EGR is showing a number that's too high.
The EGR (Exhaust Gas Recirculation) system reduces emissions by recirculating a portion of the exhaust gases back into the engine cylinders. The EGR temperature sensor monitors the temperature of the gases. A 'circuit high' code indicates the sensor is reporting a higher than expected temperature.
The P040D code is triggered when the Powertrain Control Module (PCM) detects a voltage signal from the EGR temperature sensor that is above the expected range. This could be due to a malfunctioning sensor, wiring issues, or a fault in the EGR system.
• Check Engine Light is on
• Poor engine performance
• Increased emissions
• Faulty EGR temperature sensor
• Wiring issues such as shorts or open circuits
• Faulty PCM
EGR: Exhaust Gas Recirculation
PCM: Powertrain Control Module
• Inspect the EGR temperature sensor and its wiring for damage.
• Use a multimeter to check the voltage and resistance of the sensor.
• Check the PCM for any faults or updates.
• Replace the EGR temperature sensor if faulty.
• Repair or replace damaged wiring or connectors.
• Reprogram or replace the PCM if necessary.
• OBD-II scanner
• Multimeter
• Wrench set
$100 - $300
Moderate
• Ford F-150
• Chevrolet Silverado
• Dodge Ram
• Regular maintenance of the EGR system
• Ensure wiring and connectors are in good condition
• Use quality fuel to reduce carbon buildup
Sensor Issue
• Have the vehicle inspected by a professional mechanic.
• Avoid driving for extended periods with the Check Engine Light on.
Check with your vehicle manufacturer for warranty coverage on emissions-related components.
The P040D code has been associated with EGR system issues, particularly in vehicles with high mileage or poor maintenance.
Moderate – Addressing this issue promptly can prevent further engine performance problems.
Driving with a malfunctioning EGR system can increase emissions and may not comply with local emissions regulations.
• Engine at operating temperature
• Vehicle in a safe, stationary position
The EGR temperature sensor is typically located near the EGR valve on the engine.
Q: What does the EGR temperature sensor do?
A: It measures the temperature of the exhaust gases being recirculated by the EGR system.
Q: Can I drive with a P040D code?
A: It's not recommended as it can lead to increased emissions and engine performance issues.
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