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 system that helps clean the car's exhaust has too much pressure. It's like when you blow too hard into a balloon and it feels like it might pop.
The P20E9 code is triggered when the reductant system, which is part of the vehicle's emissions control system, detects that the pressure in the reductant line is higher than the specified limit.
The reductant system, commonly known as the Diesel Exhaust Fluid (DEF) system, is used to reduce emissions in diesel engines. The system injects DEF into the exhaust stream to convert harmful NOx emissions into harmless nitrogen and water. The pressure sensor in the system monitors the pressure of the DEF fluid, and if it detects a pressure higher than the threshold, it triggers the P20E9 code.
• Check Engine Light is on
• Poor engine performance
• Possible reduction in fuel efficiency
• Faulty reductant pressure sensor
• Blocked or kinked DEF line
• Malfunctioning DEF pump
Reductant: A fluid, typically Diesel Exhaust Fluid (DEF), used to reduce emissions in diesel engines.
DEF: Diesel Exhaust Fluid, a solution used in Selective Catalytic Reduction (SCR) systems to reduce NOx emissions.
• Use an OBD-II scanner to confirm the P20E9 code.
• Inspect the DEF lines for blockages or kinks.
• Test the reductant pressure sensor for proper operation.
• Replace the reductant pressure sensor if faulty.
• Clear any blockages in the DEF line.
• Replace or repair the DEF pump if necessary.
• OBD-II scanner
• Multimeter
• Wrench set
$150 - $500
Moderate
• Ford F-250
• Chevrolet Silverado 2500
• Ram 2500
• Regularly check and maintain the DEF system.
• Use high-quality DEF fluid.
• Inspect DEF lines for wear and tear.
Emissions Control Issue
• Do not ignore the Check Engine Light; address the issue promptly.
• Ensure regular maintenance of the DEF system.
• Consult a professional mechanic if unsure about repairs.
Check with your vehicle manufacturer, as emissions-related components may have extended warranties.
This code has become more common with the increased use of DEF systems in diesel vehicles to meet stricter emissions standards.
Moderate – While the vehicle may still be drivable, it's important to address this issue to avoid increased emissions and potential damage to the DEF system.
Driving with a malfunctioning emissions system may not comply with emissions regulations and could result in fines.
• Engine running
• DEF system pressurized
The reductant pressure sensor is typically located near the DEF tank or along the DEF line.
Q: Can I drive with the P20E9 code?
A: It is possible to drive with this code, but it's not recommended as it may lead to increased emissions and potential damage to the DEF system.
Q: How often should I check my DEF system?
A: It's advisable to check your DEF system during regular vehicle maintenance or if you notice any warning lights or performance issues.
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