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 has detected a problem with the sensor that measures the temperature of the fluid used to reduce pollution in diesel engines. It's like a thermometer for a special tank in the car, and it's not working right.
The P205B code is triggered when the Engine Control Module (ECM) detects that the reductant tank temperature sensor's readings are out of the expected range or performance.
The reductant tank temperature sensor monitors the temperature of the DEF (Diesel Exhaust Fluid) in the tank. This sensor ensures that the fluid is at an optimal temperature for effective NOx reduction. If the sensor sends a signal that is outside the normal range, the ECM sets the P205B code.
• Check Engine Light is on
• Possible reduction in engine performance
• Increased emissions
• Faulty reductant tank temperature sensor
• Wiring issues such as shorts or open circuits
• Defective ECM
ECM: Engine Control Module
DEF: Diesel Exhaust Fluid
NOx: Nitrogen Oxides, a group of harmful pollutants
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors related to the sensor.
• Test the sensor's resistance and voltage output.
• Replace the reductant tank temperature sensor.
• Repair or replace damaged wiring or connectors.
• Reprogram or replace the ECM if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $400
Moderate
• Ford F-250
• Chevrolet Silverado
• Ram 2500
• Regularly inspect and maintain the DEF system.
• Ensure proper DEF fluid levels.
• Check for any wiring damage periodically.
Sensor Issue
• Do not ignore the Check Engine Light.
• Have the vehicle inspected by a professional if unsure.
• Regular maintenance can prevent such issues.
Check with the vehicle manufacturer for warranty coverage on emissions-related components.
P205B has been a common code in diesel vehicles equipped with DEF systems since stricter emissions standards were implemented.
Moderate – Addressing this issue promptly can prevent further emissions violations and maintain engine performance.
Driving with a malfunctioning emissions system can lead to increased pollution and may not comply with local emissions regulations.
• Engine at operating temperature
• Vehicle in a safe, stationary position
The reductant tank temperature sensor is typically located in or near the DEF tank, which is usually at the rear of the vehicle.
Q: Can I drive with a P205B code?
A: While the vehicle may still operate, it's best to address the issue to avoid increased emissions and potential engine performance problems.
Q: How do I reset the Check Engine Light after fixing the issue?
A: After repairs, use an OBD-II scanner to clear the code. If the issue is resolved, the light should stay off.
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