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 part of the car that helps control the air pressure for injecting a special fluid into the exhaust to make it cleaner. It's like when a straw has a hole in it and you can't drink your juice properly.
The P20A6 code indicates an issue with the circuit controlling the air pressure valve for the reductant injection system, which is part of the vehicle's emissions control system.
P20A6 is triggered when the Engine Control Module (ECM) detects an open circuit or malfunction in the reductant injection air pressure control valve circuit. This valve is crucial for maintaining the correct air pressure needed to inject the reductant (usually Diesel Exhaust Fluid) into the exhaust system to reduce emissions.
• Check Engine Light is on
• Decreased fuel efficiency
• Increased emissions
• Faulty reductant injection air pressure control valve
• Open or shorted wiring in the valve circuit
• Faulty ECM
Reductant: A fluid used to reduce emissions, often Diesel Exhaust Fluid (DEF).
ECM: Engine Control Module, the computer that manages engine functions.
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors for damage or corrosion.
• Test the reductant injection air pressure control valve for proper operation.
• Repair or replace damaged wiring or connectors.
• Replace the faulty reductant injection air pressure control valve.
• Reprogram or replace the ECM if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $500
Moderate
• Ford F-250
• Chevrolet Silverado
• Dodge Ram 2500
• Regularly inspect and maintain the exhaust system.
• Ensure proper fluid levels in the reductant tank.
• Schedule routine vehicle diagnostics.
Sensor Issue
• Avoid driving long distances until the issue is resolved.
• Consult with a professional mechanic for accurate diagnosis.
Check if your vehicle's emissions system is covered under warranty.
This code has become more common with the introduction of stricter emissions standards and the increased use of Diesel Exhaust Fluid systems.
Moderate – While the vehicle may still operate, emissions will be higher, and fuel efficiency may decrease.
Driving with this code may result in failing emissions tests, which can be illegal in some areas.
• Engine running
• Vehicle at operating temperature
The reductant injection air pressure control valve is typically located near the exhaust system, often close to the reductant tank or pump.
Q: Can I drive with the P20A6 code?
A: While you can drive with this code, it's not recommended as it may lead to increased emissions and reduced fuel efficiency.
Q: How can I prevent this code from appearing?
A: Regular maintenance and inspections of the exhaust and reductant systems can help prevent this issue.
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