Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means there's a problem with the car's system that helps clean up the exhaust. It's like when a hose isn't giving enough water to a plant; here, the car isn't getting enough fuel to clean the exhaust properly.
The P20D9 code indicates that the engine control module (ECM) has detected a low voltage or signal in the circuit responsible for supplying fuel to the exhaust aftertreatment system.
The exhaust aftertreatment system in modern vehicles often uses a small amount of fuel to help reduce emissions. The P20D9 code is triggered when the ECM detects that the voltage or signal in the fuel supply control circuit is below the expected range, indicating a potential issue with the fuel delivery to the aftertreatment system.
• Check Engine Light illuminated
• Decreased fuel efficiency
• Increased emissions
• Faulty fuel supply control circuit
• Damaged or corroded wiring or connectors
• Failed exhaust aftertreatment fuel injector
ECM: Engine Control Module
Aftertreatment: A system used to reduce emissions from the exhaust of an engine
• Perform a visual inspection of the wiring and connectors related to the fuel supply control circuit.
• Use a multimeter to check for proper voltage and continuity in the circuit.
• Test the exhaust aftertreatment fuel injector for proper operation.
• Repair or replace damaged wiring or connectors.
• Replace the exhaust aftertreatment fuel injector if faulty.
• Clear the code and test drive to ensure the issue is resolved.
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $500
Moderate
• Ford F-250
• Chevrolet Silverado
• Ram 2500
• Regular maintenance checks of the exhaust system
• Ensure quality fuel is used
• Keep electrical connections clean and secure
Sensor Issue
• Have the vehicle inspected by a professional if the Check Engine Light is on.
• Avoid driving the vehicle extensively until the issue is resolved to prevent further damage.
Check with your vehicle manufacturer as emissions-related components often have extended warranties.
The P20D9 code has become more common with the increased use of advanced emission control systems in diesel vehicles.
Moderate – It should be addressed soon to prevent increased emissions and potential damage to the exhaust system.
Ignoring this code can lead to failing emissions tests and contribute to environmental pollution.
• Engine at operating temperature
• Vehicle in a safe, stationary position
The exhaust aftertreatment fuel supply components are typically located near the exhaust system, often under the vehicle.
Q: Can I drive with a P20D9 code?
A: While the vehicle may still operate, it's not advisable to drive extensively as it can lead to increased emissions and potential damage to the exhaust system.
Q: How can I prevent a P20D9 code?
A: Regular maintenance and using quality fuel can help prevent issues with the exhaust aftertreatment system.
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