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 thinks a part that controls the stuff used to clean the exhaust turned off too soon.
The P20EA code indicates that the power relay for the reductant control module, which is responsible for controlling the diesel exhaust fluid (DEF) system, has de-energized or turned off earlier than expected.
The reductant control module manages the delivery of diesel exhaust fluid (DEF) to the exhaust system to reduce emissions. The power relay for this module should remain energized to ensure proper operation. If it de-energizes too early, it can disrupt the DEF system's function, leading to increased emissions and potential vehicle performance issues.
• Check engine light is on
• Possible increase in emissions
• Potential reduction in engine performance
• Faulty reductant control module power relay
• Wiring issues or poor connections
• Defective reductant control module
Reductant: A substance used to reduce emissions, such as diesel exhaust fluid (DEF).
Relay: An electrical switch that opens and closes under the control of another electrical circuit.
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connections to the reductant control module.
• Test the power relay for proper operation.
• Replace the faulty power relay.
• Repair or replace damaged wiring.
• Replace the reductant control module if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $500
Moderate
• Ford F-250
• Chevrolet Silverado
• Ram 2500
• Regularly inspect and maintain the DEF system.
• Ensure all electrical connections are secure.
• Use quality DEF fluid.
Emission Control
• Have the vehicle inspected by a professional.
• Avoid ignoring the check engine light.
• Maintain regular service intervals for the DEF system.
Check with your vehicle manufacturer; emissions-related components may be covered under warranty.
This code has become more common with the increased use of DEF systems in diesel vehicles to meet stricter emissions standards.
Moderate – Addressing this issue can prevent increased emissions and potential engine performance problems.
Ignoring emissions-related issues can lead to failing emissions tests and potential fines.
• Engine running
• DEF system active
The reductant control module is typically located near the DEF tank or in the engine compartment.
Q: Can I drive with a P20EA code?
A: It's possible to drive, but it's best to fix the issue to avoid increased emissions and potential engine performance problems.
Q: What happens if I ignore the P20EA code?
A: Ignoring the code can lead to higher emissions, potential fines, and reduced engine performance over time.
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