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 heats up the fluid used to clean the car's exhaust. It's like when a heater in your house doesn't work properly.
The P223B code is triggered when the Engine Control Module (ECM) detects a problem with the control circuit of the reductant heater. This heater is used to warm up the diesel exhaust fluid (DEF) to ensure it works properly in reducing emissions.
The reductant heater is part of the Selective Catalytic Reduction (SCR) system in diesel engines. It ensures that the diesel exhaust fluid remains at an optimal temperature for effective NOx reduction. The P223B code indicates an issue with the electrical circuit controlling this heater, which could be due to a fault in the heater itself, wiring issues, or a problem with the ECM.
• Check Engine Light is on
• Poor fuel efficiency
• Increased emissions
• Faulty reductant heater
• Damaged wiring or connectors
• Faulty ECM
ECM: Engine Control Module
SCR: Selective Catalytic Reduction
DEF: Diesel Exhaust Fluid
• Scan the vehicle for codes and note any other related codes.
• Inspect the wiring and connectors for damage or corrosion.
• Test the reductant heater for proper resistance and operation.
• Replace the reductant heater if faulty.
• Repair or replace damaged wiring or connectors.
• Reprogram or replace the ECM if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$200 - $600
Moderate
• Ford F-250
• Chevrolet Silverado 2500
• Ram 2500
• Regularly inspect and maintain the SCR system.
• Ensure proper quality and levels of diesel exhaust fluid.
• Conduct regular vehicle diagnostics.
Sensor Issue
• Address the issue promptly to avoid increased emissions.
• Consult a professional mechanic for accurate diagnosis and repair.
Check with the vehicle manufacturer for warranty coverage on emissions-related components.
This code has become more common with the increased use of SCR systems in diesel vehicles to meet stricter emissions standards.
Moderate – While the vehicle may still be drivable, it could lead to increased emissions and fuel consumption.
Ignoring emissions-related issues can lead to failing emissions tests and potential fines.
• Engine at operating temperature
• Vehicle in a safe and well-ventilated area
The reductant heater is typically located near the DEF tank or along the DEF line.
Q: Can I drive my car with a P223B code?
A: Yes, but it's not recommended as it can lead to increased emissions and potential damage to the SCR system.
Q: How can I prevent this code from appearing?
A: Regular maintenance of the SCR system and using quality DEF can help prevent issues.
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