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 sensor that tells the car how warm or cold the special fluid tank is. It's like when a thermometer breaks and can't tell you the temperature.
The P205A code is triggered when the Engine Control Module (ECM) detects a malfunction in the circuit of the reductant tank temperature sensor.
The reductant tank temperature sensor is used to monitor the temperature of the diesel exhaust fluid (DEF) in the tank. This information is crucial for the proper functioning of the Selective Catalytic Reduction (SCR) system, which reduces emissions. A fault in this sensor's circuit can lead to incorrect temperature readings, affecting the SCR system's performance.
• Check Engine Light illuminated
• Possible increase in emissions
• Potential decrease in fuel efficiency
• Faulty reductant tank temperature sensor
• Damaged wiring or connectors in the sensor circuit
• Defective Engine Control Module (ECM)
Reductant: A substance used to reduce emissions, commonly diesel exhaust fluid.
SCR: Selective Catalytic Reduction, a system that reduces emissions in diesel engines.
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors for damage or corrosion.
• Test the reductant tank temperature sensor for proper operation.
• Replace the reductant tank temperature sensor if faulty.
• Repair or replace damaged wiring or connectors.
• Reprogram or replace the ECM if necessary.
• OBD-II scanner
• Digital multimeter
• Basic hand tools
$150 - $400
Moderate
• Ford F-Series
• Chevrolet Silverado
• Dodge Ram
• Regularly inspect wiring and connectors for damage.
• Ensure the DEF tank is filled with quality fluid.
• Perform regular maintenance checks on the SCR system.
Sensor Issue
• Do not ignore the Check Engine Light.
• Have the vehicle inspected by a professional mechanic.
• Avoid using low-quality DEF fluid.
Check with your vehicle manufacturer for specific warranty coverage on emissions-related components.
This code has become more common with the increased use of diesel engines and stricter emissions standards.
Moderate – While the vehicle may still be drivable, emissions and fuel efficiency could be affected.
Operating a vehicle with a malfunctioning emissions system may violate local emissions regulations.
• Engine at operating temperature
• Vehicle in a safe, stationary position
The reductant tank temperature sensor is typically located on or near the diesel exhaust fluid tank, usually at the rear of the vehicle.
Q: Can I drive with a P205A code?
A: Yes, but it's recommended to fix the issue soon to avoid increased emissions and potential damage to the SCR system.
Q: What happens if I ignore this code?
A: Ignoring the code can lead to higher emissions, reduced fuel efficiency, and potential damage to the emissions system.
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